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Sample records for tendons structural

  1. Collagen Structure of Tendon Relates to Function

    Directory of Open Access Journals (Sweden)

    Marco Franchi

    2007-01-01

    Full Text Available A tendon is a tough band of fibrous connective tissue that connects muscle to bone, designed to transmit forces and withstand tension during muscle contraction. Tendon may be surrounded by different structures: 1 fibrous sheaths or retinaculae; 2 reflection pulleys; 3 synovial sheaths; 4 peritendon sheaths; 5 tendon bursae. Tendons contain a few cells, mostly represented by tenoblasts along with endothelial cells and some chondrocytes; b proteoglycans (PGs, mainly decorin and hyaluronan, and c collagen, mostly type I. Tendon is a good example of a high ordered extracellular matrix in which collagen molecules assemble into filamentous collagen fibrils (formed by microfibrils which aggregate to form collagen fibers, the main structural components. It represents a multihierarchical structure as it contains collagen molecules arranged in fibrils then grouped in fibril bundles, fascicles and fiber bundles that are almost parallel to the long axis of the tendon, named as primary, secondary and tertiary bundles. Collagen fibrils in tendons show prevalently large diameter, a D-period of about 67 nm and appear built of collagen molecules lying at a slight angle (< 5°. Under polarized light microscopy the collagen fiber bundles appear crimped with alternative dark and light transverse bands. In recent studies tendon crimps observed via SEM and TEM show that the single collagen fibrils suddenly changing their direction contain knots. These knots of collagen fibrils inside each tendon crimp have been termed “fibrillar crimps”, and even if they show different aspects they all may fulfil the same functional role. As integral component of musculoskeletal system, the tendon acts to transmit muscle forces to the skeletal system. There is no complete understanding of the mechanisms in transmitting/absorbing tensional forces within the tendon; however it seems likely that a flattening of tendon crimps may occur at a first stage of tendon stretching

  2. Sex differences in tendon structure and function.

    Science.gov (United States)

    Sarver, Dylan C; Kharaz, Yalda Ashraf; Sugg, Kristoffer B; Gumucio, Jonathan P; Comerford, Eithne; Mendias, Christopher L

    2017-10-01

    Tendons play a critical role in the transmission of forces between muscles and bones, and chronic tendon injuries and diseases are among the leading causes of musculoskeletal disability. Little is known about sex-based differences in tendon structure and function. Our objective was to evaluate the mechanical properties, biochemical composition, transcriptome, and cellular activity of plantarflexor tendons from 4 month old male and female C57BL/6 mice using in vitro biomechanics, mass spectrometry-based proteomics, genome-wide expression profiling, and cell culture techniques. While the Achilles tendons of male mice were approximately 6% larger than female mice (p differences in mechanical properties (p > 0.05) of plantaris tendons were observed. Mass spectrometry proteomics analysis revealed no significant difference between sexes in the abundance of major extracellular matrix (ECM) proteins such as collagen types I (p = 0.30) and III (p = 0.68), but female mice had approximately twofold elevations (p differed by only 1%. In vitro, neither the sex of the serum that fibroblasts were cultured in, nor the sex of the ECM in which they were embedded, had profound effects on the expression of collagen and cell proliferation genes. Our results indicate that while male mice expectedly had larger tendons, male and female tendons have very similar mechanical properties and biochemical composition, with small increases in some ECM proteins and proteoglycans evident in female tendons. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2117-2126, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  3. Functionally Distinct Tendons From Elastin Haploinsufficient Mice Exhibit Mild Stiffening and Tendon-Specific Structural Alteration.

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    Eekhoff, Jeremy D; Fang, Fei; Kahan, Lindsey G; Espinosa, Gabriela; Cocciolone, Austin J; Wagenseil, Jessica E; Mecham, Robert P; Lake, Spencer P

    2017-11-01

    Elastic fibers are present in low quantities in tendon, where they are located both within fascicles near tenocytes and more broadly in the interfascicular matrix (IFM). While elastic fibers have long been known to be significant in the mechanics of elastin-rich tissue (i.e., vasculature, skin, lungs), recent studies have suggested a mechanical role for elastic fibers in tendons that is dependent on specific tendon function. However, the exact contribution of elastin to properties of different types of tendons (e.g., positional, energy-storing) remains unknown. Therefore, this study purposed to evaluate the role of elastin in the mechanical properties and collagen alignment of functionally distinct supraspinatus tendons (SSTs) and Achilles tendons (ATs) from elastin haploinsufficient (HET) and wild type (WT) mice. Despite the significant decrease in elastin in HET tendons, a slight increase in linear stiffness of both tendons was the only significant mechanical effect of elastin haploinsufficiency. Additionally, there were significant changes in collagen nanostructure and subtle alteration to collagen alignment in the AT but not the SST. Hence, elastin may play only a minor role in tendon mechanical properties. Alternatively, larger changes to tendon mechanics may have been mitigated by developmental compensation of HET tendons and/or the role of elastic fibers may be less prominent in smaller mouse tendons compared to the larger bovine and human tendons evaluated in previous studies. Further research will be necessary to fully elucidate the influence of various elastic fiber components on structure-function relationships in functionally distinct tendons.

  4. Is higher serum cholesterol associated with altered tendon structure or tendon pain? A systematic review.

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    Tilley, Benjamin J; Cook, Jill L; Docking, Sean I; Gaida, James E

    2015-12-01

    Tendon pain occurs in individuals with extreme cholesterol levels (familial hypercholesterolaemia). It is unclear whether the association with tendon pain is strong with less extreme elevations of cholesterol. To determine whether lipid levels are associated with abnormal tendon structure or the presence of tendon pain. We conducted a systematic review and meta-analysis. Relevant articles were found through an electronic search of 6 medical databases-MEDLINE, Cochrane, AMED, EMBASE, Web of Science and Scopus. We included all case-control or cross-sectional studies with data describing (1) lipid levels or use of lipid-lowering drugs and (2) tendon structure or tendon pain. 17 studies (2612 participants) were eligible for inclusion in the review. People with altered tendon structure or tendon pain had significantly higher total cholesterol, low-density lipoprotein cholesterol and triglycerides, as well as lower high-density lipoprotein cholesterol; with mean difference values of 0.66, 1.00, 0.33, and -0.19 mmol/L, respectively. The results of this review indicate that a relationship exists between an individual's lipid profile and tendon health. However, further longitudinal studies are required to determine whether a cause and effect relationship exists between tendon structure and lipid levels. This could lead to advancement in the understanding of the pathoaetiology and thus treatment of tendinopathy. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  5. Converting round tendons to flat tendon constructs: Does the preparation process have an influence on the structural properties?

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    Domnick, C; Herbort, M; Raschke, M J; Schliemann, B; Siebold, R; Śmigielski, R; Fink, C

    2017-05-01

    The structural properties of hamstring tendon grafts were evaluated in a porcine model, after processing it to a flat shape, to better replace or augment anatomic flat structures (e.g. ACL, MPFL or MCL). In this biomechanical study, porcine flexor tendons were used which have a comparable shape to semitendinosus and gracilis tendons. One part of the tendon was prepared to a flat tendon construct by splitting the tendon longitudinally with a knife to half of the diameter of the tendon. The semi-split tendon was scratched out to a flat shape. The other matched part was tested in its original round shape. The tendons (n = 40) have been fixed in a uniaxial testing machine (Zwick/Roell) by cryo-clamps after preparing the fixed ends by 2-0 polyester sutures (2-0 Ethibond(®) EXCEL, Ethicon, Somerville, NJ). In every specimen, there was a free 60-mm tendon part between both clamps. The tendons have been loaded to failure to evaluate typical biomechanical parameters such as stiffness, yield load and maximum load. No statistically significant differences (n.s.) regarding stiffness, yield load and maximum load between natively round and processed flat tendons could be detected. A prepared flat-shaped tendon does not show any different structural properties compared with an original round tendon. Therefore, a flat tendon seems to be a biomechanical stable graft option for anatomic reconstruction or augmentation of injured natively flat-shaped structures such as MCL, MPFL or ACL.

  6. Structural tendon changes in patients with acromegaly: assessment of Achilles tendon with sonoelastography.

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    Onal, Eda Demil; Ipek, Ali; Evranos, Berna; Idilman, Ilkay Sedakat; Cakir, Bekir; Ersoy, Reyhan

    2016-03-01

    To describe the sonoelastographic appearance of the Achilles tendon in acromegalic patients and to determine whether the blood concentrations of growth hormone (GH) and insulin-like growth factor (IGF-1) are associated with the various sonographic elasticity types of Achilles tendons. Eighty-four Achilles tendons of 42 acromegaly patients and 84 Achilles tendons of 42 healthy volunteers were assessed with sonoelastography. The tendons were classified into two main types according to the elasticity features: type 1 blue/green (hard tissue) and type 2 yellow/red within green (intermediate-soft tissue). Two subtypes of these types were also defined. According to the definition, the elasticity of the tissue was in a spectrum ranging from hard to soft as the type progressed from 1a to 2b. The mean thickness of Achilles tendons in patients with acromegaly was significantly higher compared with healthy Achilles tendons (5.1+/-0.7 mm vs. 4.4+/-0.5, pAchilles tendons (5.5+/-0.8 mm vs. 4.8+/-0.5 mm in inactive disease, p=0.003). A significantly higher proportion of acromegaly patients had type 2 sonoelastographic appearance of the Achilles tendon (124/252 third; 49.2% vs. 81/252 third; 32.1%, p=0.0001). Activity status of acromegaly and GH/IGF-I levels were similar in patients with different types of elasticity (p>0.05). Sonoelastography revealed structural changes in the tendinous tissue of patients with acromegaly, but it was not sensitive enough to reflect changes in the serum levels of GH/IGF-1.

  7. Time-Dependent Alterations of MMPs, TIMPs and Tendon Structure in Human Achilles Tendons after Acute Rupture.

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    Minkwitz, Susann; Schmock, Aysha; Kurtoglu, Alper; Tsitsilonis, Serafeim; Manegold, Sebastian; Wildemann, Britt; Klatte-Schulz, Franka

    2017-10-20

    A balance between matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) is required to maintain tendon homeostasis. Variation in this balance over time might impact on the success of tendon healing. This study aimed to analyze structural changes and the expression profile of MMPs and TIMPs in human Achilles tendons at different time-points after rupture. Biopsies from 37 patients with acute Achilles tendon rupture were taken at surgery and grouped according to time after rupture: early (2-4 days), middle (5-6 days), and late (≥7 days), and intact Achilles tendons served as control. The histological score increased from the early to the late time-point after rupture, indicating the progression towards a more degenerative status. In comparison to intact tendons, qRT-PCR analysis revealed a significantly increased expression of MMP-1, -2, -13, TIMP-1, COL1A1, and COL3A1 in ruptured tendons, whereas TIMP-3 decreased. Comparing the changes over time post rupture, the expression of MMP-9, -13, and COL1A1 significantly increased, whereas MMP-3 and -10 expression decreased. TIMP expression was not significantly altered over time. MMP staining by immunohistochemistry was positive in the ruptured tendons exemplarily analyzed from early and late time-points. The study demonstrates a pivotal contribution of all investigated MMPs and TIMP-1, but a minor role of TIMP-2, -3, and -4, in the early human tendon healing process.

  8. Time-Dependent Alterations of MMPs, TIMPs and Tendon Structure in Human Achilles Tendons after Acute Rupture

    Science.gov (United States)

    Minkwitz, Susann; Schmock, Aysha; Kurtoglu, Alper; Tsitsilonis, Serafeim; Manegold, Sebastian; Klatte-Schulz, Franka

    2017-01-01

    A balance between matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) is required to maintain tendon homeostasis. Variation in this balance over time might impact on the success of tendon healing. This study aimed to analyze structural changes and the expression profile of MMPs and TIMPs in human Achilles tendons at different time-points after rupture. Biopsies from 37 patients with acute Achilles tendon rupture were taken at surgery and grouped according to time after rupture: early (2–4 days), middle (5–6 days), and late (≥7 days), and intact Achilles tendons served as control. The histological score increased from the early to the late time-point after rupture, indicating the progression towards a more degenerative status. In comparison to intact tendons, qRT-PCR analysis revealed a significantly increased expression of MMP-1, -2, -13, TIMP-1, COL1A1, and COL3A1 in ruptured tendons, whereas TIMP-3 decreased. Comparing the changes over time post rupture, the expression of MMP-9, -13, and COL1A1 significantly increased, whereas MMP-3 and -10 expression decreased. TIMP expression was not significantly altered over time. MMP staining by immunohistochemistry was positive in the ruptured tendons exemplarily analyzed from early and late time-points. The study demonstrates a pivotal contribution of all investigated MMPs and TIMP-1, but a minor role of TIMP-2, -3, and -4, in the early human tendon healing process. PMID:29053586

  9. FRP tendon anchorage in post-tensioned concrete structures

    DEFF Research Database (Denmark)

    Schmidt, Jacob Wittrup; Täljsten, Björn; Bennitz, Anders

    2008-01-01

    Strengthening of building structures by the use of various external post-tensioning steel tendon systems, is known to be a very efficient method. However, FRP as material in external post-tensioning projects has been investigated during the last decade. The advantages for this material are the high...

  10. The structural and mechanical properties of the Achilles tendon 2 years after surgical repair.

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    Geremia, Jeam Marcel; Bobbert, Maarten Frank; Casa Nova, Mayra; Ott, Rafael Duvelius; Lemos, Fernando de Aguiar; Lupion, Raquel de Oliveira; Frasson, Viviane Bortoluzzi; Vaz, Marco Aurélio

    2015-06-01

    Acute ruptures of the Achilles tendon affect the tendon's structural and mechanical properties. The long-term effects of surgical repair on these properties remain unclear. To evaluate effects of early mobilization versus traditional immobilization rehabilitation programs 2 years after surgical Achilles tendon repair, by comparing force-elongation and stress-strain relationships of the injured tendon to those of the uninjured tendon. A group of males with previous Achilles tendon rupture (n=18) and a group of healthy male controls (n=9) participated. Achilles tendon rupture group consisted of patients that had received early mobilization (n=9) and patients that had received traditional immobilization with a plaster cast (n=9). Comparisons of tendon structural and mechanical properties were made between Achilles tendon rupture and healthy control groups, and between the uninjured and injured sides of the two rehabilitation groups in Achilles tendon rupture group. Ultrasound was used to determine bilaterally tendon cross-sectional area, tendon resting length, and tendon elongation as a function of torque during maximal voluntary plantar flexion. From these data, Achilles tendon force-elongation and stress-strain relationships were determined. The Achilles tendon rupture group uninjured side was not different from healthy control group. Structural and mechanical parameters of the injured side were not different between the Achilles tendon rupture early mobilization and the immobilization groups. Compared to the uninjured side, the injured side showed a reduction in stress at maximal voluntary force, in Young's modulus and in stiffness. Two years post-surgical repair, the Achilles tendon mechanical properties had not returned to the uninjured contralateral tendon values. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Evidence of structurally continuous collagen fibrils in tendon

    DEFF Research Database (Denmark)

    Svensson, Rene B; Herchenhan, Andreas; Starborg, Tobias

    2017-01-01

    in this structure-function relationship is the collagen fibril length. During embryogenesis short fibrils are produced but they grow rapidly with maturation. There is some controversy regarding fibril length in adult tendon, with mechanical data generally supporting discontinuity while structural investigations...... favor continuity. This study initially set out to trace the full length of individual fibrils in adult human tendons, using serial block face-scanning electron microscopy. But even with this advanced technique the required length could not be covered. Instead a statistical approach was used on a large...... fibrils was confirmed. In light of these results, possible mechanisms that could reconcile the opposing findings on fibril continuity are discussed. STATEMENT OF SIGNIFICANCE: Connective tissues hold all parts of the body together and are mostly constructed from thin threads of the protein collagen...

  12. Biomechanical and structural response of healing Achilles tendon to fatigue loading following acute injury.

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    Freedman, Benjamin R; Sarver, Joseph J; Buckley, Mark R; Voleti, Pramod B; Soslowsky, Louis J

    2014-06-27

    Achilles tendon injuries affect both athletes and the general population, and their incidence is rising. In particular, the Achilles tendon is subject to dynamic loading at or near failure loads during activity, and fatigue induced damage is likely a contributing factor to ultimate tendon failure. Unfortunately, little is known about how injured Achilles tendons respond mechanically and structurally to fatigue loading during healing. Knowledge of these properties remains critical to best evaluate tendon damage induction and the ability of the tendon to maintain mechanical properties with repeated loading. Thus, this study investigated the mechanical and structural changes in healing mouse Achilles tendons during fatigue loading. Twenty four mice received bilateral full thickness, partial width excisional injuries to their Achilles tendons (IACUC approved) and twelve tendons from six uninjured mice were used as controls. Tendons were fatigue loaded to assess mechanical and structural properties simultaneously after 0, 1, 3, and 6 weeks of healing using an integrated polarized light system. Results showed that the number of cycles to failure decreased dramatically (37-fold, ptendon structural properties, the apparent birefringence was able to best predict dynamic modulus (R(2)=0.88-0.92) throughout healing and fatigue life. This study reinforces the concept that fatigue loading is a sensitive metric to assess tendon healing and demonstrates potential structural metrics to predict mechanical properties. © 2013 Published by Elsevier Ltd.

  13. Effect of estrogen on tendon collagen synthesis, tendon structural characteristics, and biomechanical properties in postmenopausal women

    DEFF Research Database (Denmark)

    Hansen, M.; Kongsgaard, M; Holm, Lars

    2009-01-01

    therapy (ERT, n = 10) were studied at rest and in response to one-legged resistance exercise. Synthesis of tendon collagen was determined by stable isotope incorporation [fractional synthesis rate (FSR)] and microdialysis technique (NH(2)-terminal propeptide of type I collagen synthesis). Tendon area...

  14. Structural and mechanical properties of the human Achilles tendon: Sex and strength effects.

    Science.gov (United States)

    Morrison, Sidney M; Dick, Taylor J M; Wakeling, James M

    2015-09-18

    Tendons are elastic structures that connect muscle to the skeletal system and transmit force relative to the amount of stretch they experience. The mechanical properties of human tendons are difficult to measure non-invasively, so generic values are often assumed in musculoskeletal models to represent all subjects. We aimed to determine the in vivo mechanical properties of the human Achilles tendon by calculating tendon stiffness and resting length in 10 male and 10 female trained cyclists. B-mode ultrasound coupled with motion capture was used to track the tendon lengths for the medial and lateral gastrocnemii concurrently with ankle torque measurements during ramped isometric contractions. Achilles tendon stiffness was calculated as the slope of the linear portion of the force-length curve, and this was extrapolated to zero force to yield the tendon resting length. Average Achilles tendon stiffness was 201.8 ± 5.9 N mm(-1). There was no difference in Achilles tendon stiffness or maximum isometric force between males and females, however tendon stiffness varied between individuals. The resting lengths of the MG and LG tendon were 0.209 ± 0.002 m and 0.222 ± 0.002 m respectively, and regression models determined that shank length was the best predictor of resting tendon length. Our results indicate that Achilles tendon stiffness varies with muscle strength and not sex. The variability in Achilles tendon stiffness between subjects support the need for experimentally measured subject-specific tendon properties as input parameters to improve the accuracy of musculoskeletal models. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Effects of Training Load and Leg Dominance on Achilles and Patellar Tendon Structure.

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    Esmaeili, Alireza; Stewart, Andrew M; Hopkins, William G; Elias, George P; Aughey, Robert J

    2017-04-01

    Detrimental changes in tendon structure increase the risk of tendinopathies. The aim of this study was to investigate the influence of individual internal and external training loads and leg dominance on changes in the Achilles and patellar tendon structure. The internal structure of the Achilles and patellar tendons of both limbs of 26 elite Australian footballers was assessed using ultrasound tissue characterization at the beginning and the end of an 18-wk preseason. Linear-regression analysis was used to estimate the effects of training load on changes in the proportion of aligned and intact tendon bundles for each side. Standardization and magnitude-based inferences were used to interpret the findings. Possibly to very likely small increases in the proportion of aligned and intact tendon bundles occurred in the dominant Achilles (initial value 81.1%; change, ±90% confidence limits 1.6%, ±1.0%), nondominant Achilles (80.8%; 0.9%, ±1.0%), dominant patellar (75.8%; 1.5%, ±1.5%), and nondominant patellar (76.8%; 2.7%, ±1.4%) tendons. Measures of training load had inconsistent effects on changes in tendon structure; eg, there were possibly to likely small positive effects on the structure of the nondominant Achilles tendon, likely small negative effects on the dominant Achilles tendon, and predominantly no clear effects on the patellar tendons. The small and inconsistent effects of training load are indicative of the role of recovery between tendon-overloading (training) sessions and the multivariate nature of the tendon response to load, with leg dominance a possible influencing factor.

  16. The structural and mechanical properties of the Achilles tendon 2 years after surgical repair

    NARCIS (Netherlands)

    Geremia, J.M.; Bobbert, M.F.; Casa Nova, M.; Ott, R.D.; De Aguiar Lemos, F.; De Oliveira Lupion, R.; Frasson, V.B.

    2015-01-01

    Background Acute ruptures of the Achilles tendon affect the tendon's structural and mechanical properties. The long-term effects of surgical repair on these properties remain unclear. Purpose To evaluate effects of early mobilization versus traditional immobilization rehabilitation programs 2 years

  17. Are Sport-Specific Profiles of Tendon Stiffness and Cross-Sectional Area Determined by Structural or Functional Integrity?

    Directory of Open Access Journals (Sweden)

    Hans-Peter Wiesinger

    Full Text Available The present study aimed to determine whether distinct sets of tendon properties are seen in athletes engaged in sports with contrasting requirements for tendon function and structural integrity. Patellar and Achilles tendon morphology and force-deformation relation were measured by combining ultrasonography, electromyography and dynamometry in elite ski jumpers, distance runners, water polo players and sedentary individuals. Tendon cross-sectional area normalized to body mass2/3 was smaller in water polo players than in other athletes (patellar and Achilles tendon; -28 to -24% or controls (patellar tendon only; -9%. In contrast, the normalized cross-sectional area was larger in runners (patellar tendon only; +26% and ski jumpers (patellar and Achilles tendon; +21% and +13%, respectively than in controls. Tendon stiffness normalized to body mass2/3 only differed in ski jumpers, compared to controls (patellar and Achilles tendon; +11% and +27%, respectively and to water polo players (Achilles tendon only; +23%. Tendon size appears as an adjusting variable to changes in loading volume and/or intensity, possibly to preserve ultimate strength or fatigue resistance. However, uncoupled morphological and mechanical properties indicate that functional requirements may also influence tendon adaptations.

  18. Coordinated development of muscles and tendon-like structures: early interactions in the Drosophila leg

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    cedric esoler

    2016-02-01

    Full Text Available The formation of the musculoskeletal system is a remarkable example of tissue assembly. In both vertebrates and invertebrates, precise connectivity between muscles and skeleton (or exoskeleton via tendons or equivalent structures is fundamental for movement and stability of the body. The molecular and cellular processes underpinning muscle formation are well established and significant advances have been made in understanding tendon development. However, the mechanisms contributing to proper connection between these two tissues have received less attention. Observations of coordinated development of tendons and muscles suggest these tissues may interact during the different steps in their development. There is growing evidence that, depending on animal model and muscle type, these interactions can take place from progenitor induction to the final step of the formation of the musculoskeletal system. Here we briefly review and compare the mechanisms behind muscle and tendon interaction throughout the development of vertebrates and Drosophila before going on to discuss our recent findings on the coordinated development of muscles and tendon-like structures in Drosophila leg. By altering apodeme formation (the functional Drosophila equivalent of tendons in vertebrates during the early steps of leg development, we affect the spatial localisation of subsequent myoblasts. These findings provide the first evidence of the developmental impact of early interactions between muscle and tendon-like precursors, and confirm the appendicular Drosophila muscle system as a valuable model for studying these processes.

  19. Structural and biochemical alterations during the healing process of tendons treated with Aloe vera.

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    Aro, A A; Nishan, U; Perez, M O; Rodrigues, R A; Foglio, M A; Carvalho, J E; Gomes, L; Vidal, B C; Pimentel, E R

    2012-10-29

    The tendon is composed of highly organized collagen fibers that form a complex supramolecular structure. After lesions, the organization and composition of the tendon are not completely restored. Our purpose was to evaluate if the application of Aloe vera improves tendon healing, considering the effectiveness in the stimulus of collagen synthesis. The calcaneal tendon of male Wistar rats was partially transected with subsequent topical application of A. vera ointment at the injury. The animals were separated into groups with tendons treated with the A. vera extract for 7days and excised on the 7th, 14th and 21st days after surgery; control rats received only ointment base without plant extract. Morphological analysis using polarization microscopy showed that the entire tendon undergoes a remodeling process, with disorganized collagen fibers by days 7 and 14 in plant-treated and non-treated groups and with a higher birefringence in tendons of the plant-treated group on the 21st day. A higher concentration of hydroxyproline was found in plant-treated tendons on days 7 and 14 compared with their controls. Western blots showed lower amounts of type I collagen in the plant-treated group on day 14 compared with the control. MMP-9 diminished 14days after lesion and the active isoform of MMP-2 increased on day 21 in plant-treated groups. The present study indicates a beneficial effect of A. vera in the tissue reorganization in the transected region of the tendon 21days after injury and is supported by an increase of active MMP-2. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Nonlinear ultrasonic guided waves for stress monitoring in prestressing tendons for post-tensioned concrete structures

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    Bartoli, Ivan; Nucera, Claudio; Srivastava, Ankit; Salamone, Salvatore; Phillips, Robert; Lanza di Scalea, Francesco; Coccia, Stefano; Sikorsky, Charles S.

    2009-03-01

    Many bridges, including 90% of the California inventory, are post-tensioned box-girders concrete structures. Prestressing tendons are the main load-carrying components of these and other post-tensioned structures. Despite their criticality, much research is needed to develop and deploy techniques able to provide real-time information on the level of prestress in order to detect dangerous stress losses. In collaboration with Caltrans, UCSD is investigating the combination of ultrasonic guided waves and embedded sensors to provide both prestress level monitoring and defect detection capabilities in concrete-embedded PS tendons. This paper presents a technique based on nonlinear ultrasonic guided waves in the 100 kHz - 2 MHz range for monitoring prestress levels in 7-wire PS tendons. The technique relies on the fact that an axial stress on the tendon generates a proportional radial stress between adjacent wires (interwire stress). In turn, the interwire stress modulates nonlinear effects in ultrasonic wave propagation through both the presence of finite strains and the interwire contact. The nonlinear ultrasonic behavior of the tendon under changing levels of prestress is monitored by tracking higher-order harmonics at (nω) arising under a fundamental guided-wave excitation at (ω). Experimental results will be presented to identify (a) ranges of fundamental excitations at (ω) producing maximum nonlinear response, and (b) optimum lay-out of the transmitting and the receiving transducers within the test tendons. Compared to alternative methods based on linear ultrasonic features, the proposed nonlinear ultrasonic technique appears more sensitive to prestress levels and more robust against changing excitation power at the transmitting transducer or changing transducer/tendon bond conditions.

  1. Experimental diabetes induces structural, inflammatory and vascular changes of Achilles tendons.

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    Rodrigo R de Oliveira

    Full Text Available This study aims to demonstrate how the state of chronic hyperglycemia from experimental Diabetes Mellitus can influence the homeostatic imbalance of tendons and, consequently, lead to the characteristics of tendinopathy. Twenty animals were randomly divided into two experimental groups: control group, consisting of healthy rats and diabetic group constituted by rats induced to Diabetes Mellitus I. After twenty-four days of the induction of Diabetes type I, the Achilles tendon were removed for morphological evaluation, cellularity, number and cross-sectional area of blood vessel, immunohistochemistry for Collagen type I, VEGF and NF-κB nuclear localization sequence (NLS and nitrate and nitrite level. The Achilles tendon thickness (µm/100g of diabetic animals was significantly increased and, similarly, an increase was observed in the density of fibrocytes and mast cells in the tendons of the diabetic group. The average number of blood vessels per field, in peritendinous tissue, was statistically higher in the diabetic group 3.39 (2.98 vessels/field when compared to the control group 0.89 (1.68 vessels/field p = 0.001 and in the intratendinous region, it was observed that blood vessels were extremely rare in the control group 0.035 (0.18 vessels/field and were often present in the tendons of the diabetic group 0.89 (0.99 vessels/field. The immunohistochemistry analysis identified higher density of type 1 collagen and increased expression of VEGF as well as increased immunostaining for NFκB p50 NLS in the nucleus in Achilles tendon of the diabetic group when compared to the control group. Higher levels of nitrite/nitrate were observed in the experimental group induced to diabetes. We conclude that experimental DM induces notable structural, inflammatory and vascular changes in the Achilles tendon which are compatible with the process of chronic tendinopathy.

  2. Health monitoring of prestressing tendons in post-tensioned concrete structures

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    Salamone, Salvatore; Bartoli, Ivan; Nucera, Claudio; Phillips, Robert; Lanza di Scalea, Francesco

    2011-04-01

    Currently 90% of bridges built in California are post-tensioned box-girder. In such structures the steel tendons are the main load-carrying components. The loss of prestress, as well as the presence of defects or the tendon breakage, can be catastrophic for the entire structure. Unfortunately, today there is no well-established method for the monitoring of prestressing (PS) tendons that can provide simultaneous information related to the presence of defects and the level of prestress in a continuous, real time manner. If such a monitoring system were available, considerable savings would be achieved in bridge maintenance since repairs would be implemented in a timely manner without traffic disruptions. This paper presents a health monitoring system for PS tendons in post-tensioned structures of interest to Caltrans. Such a system uses ultrasonic guided waves and embedded sensors to provide simultaneously and in real time, (a) measurements of the level of applied prestress, and (b) defect detection at early grow stages. The proposed PS measurement technique exploits the sensitivity of ultrasonic waves to the inter-wire contact developing in a multi-wire strand as a function of prestress level. In particular the nonlinear ultrasonic behavior of the tendon under changing levels of prestress is monitored by tracking higher-order harmonics at (nω) arising under a fundamental guided-wave excitation at (ω). Moreover this paper also present real-time damage detection and location in post-tensioned bridge joints using Acoustic Emission techniques. Experimental tests on large-scale single-tendon PT joint specimens, subjected to multiple load cycles, will be presented to validate the monitoring of PS loads (through nonlinear ultrasonic probing) and the monitoring of damage progression and location (through acoustic emission techniques). Issues and potential for the use of such techniques to monitor post-tensioned bridges in the field will be discussed.

  3. Experimental Diabetes Alters the Morphology and Nano-Structure of the Achilles Tendon.

    Science.gov (United States)

    Oliveira, Rodrigo Ribeiro de; Medina de Mattos, Rômulo; Magalhães Rebelo, Luciana; Guimarães Meireles Ferreira, Fernanda; Tovar-Moll, Fernanda; Eurico Nasciutti, Luiz; de Castro Brito, Gerly Anne

    2017-01-01

    Although of several studies that associate chronic hyperglycemia with tendinopathy, the connection between morphometric changes as witnessed by magnetic resonance (MR) images, nanostructural changes, and inflammatory markers have not yet been fully established. Therefore, the present study has as a hypothesis that the Achilles tendons of rats with diabetes mellitus (DM) exhibit structural changes. The animals were randomly divided into two experimental groups: Control Group (n = 06) injected with a vehicle (sodium citrate buffer solution) and Diabetic Group (n = 06) consisting of rats submitted to intraperitoneal administration of streptozotocin. MR was performed 24 days after the induction of diabetes and images were used for morphometry using ImageJ software. Morphology of the collagen fibers within tendons was examined using Atomic Force microscopy (AFM). An increase in the dimension of the coronal plane area was observed in the diabetic group (8.583 ± 0.646 mm2/100g) when compared to the control group (4.823 ± 0.267 mm2/100g) resulting in a significant difference (p = 0.003) upon evaluating the Achilles tendons. Similarly, our analysis found an increase in the size of the transverse section area in the diabetic group (1.328 ± 0.103 mm2/100g) in comparison to the control group (0.940 ± 0.01 mm2/100g) p = 0.021. The tendons of the diabetic group showed great irregularity in fiber bundles, including modified grain direction and jagged junctions and deformities in the form of collagen fibrils bulges. Despite the morphological changes observed in the Achilles tendon of diabetic animals, IL1 and TNF-α did not change. Our results suggest that DM promotes changes to the Achilles tendon with important structural modifications as seen by MR and AFM, excluding major inflammatory changes.

  4. Ultrasound assessment for grading structural tendon changes in supraspinatus tendinopathy: an inter-rater reliability study

    DEFF Research Database (Denmark)

    Ingwersen, Kim Gordon; Hjarbæk, John; Eshøj, Henrik

    2016-01-01

    Aim To evaluate the inter-rater reliability of measuring structural changes in the tendon of patients, clinically diagnosed with supraspinatus tendinopathy (cases) and healthy participants (controls), on ultrasound (US) images captured by standardised procedures. Methods A total of 40 participants...

  5. Composition and structure of porcine digital flexor tendon-bone insertion tissues.

    Science.gov (United States)

    Chandrasekaran, Sandhya; Pankow, Mark; Peters, Kara; Huang, Hsiao-Ying Shadow

    2017-11-01

    Tendon-bone insertion is a functionally graded tissue, transitioning from 200 MPa tensile modulus at the tendon end to 20 GPa tensile modulus at the bone, across just a few hundred micrometers. In this study, we examine the porcine digital flexor tendon insertion tissue to provide a quantitative description of its collagen orientation and mineral concentration by using Fast Fourier Transform (FFT) based image analysis and mass spectrometry, respectively. Histological results revealed uniformity in global collagen orientation at all depths, indicative of mechanical anisotropy, although at mid-depth, the highest fiber density, least amount of dispersion, and least cellular circularity were evident. Collagen orientation distribution obtained through 2D FFT of histological imaging data from fluorescent microscopy agreed with past measurements based on polarized light microscopy. Results revealed global fiber orientation across the tendon-bone insertion to be preserved along direction of physiologic tension. Gradation in the fiber distribution orientation index across the insertion was reflective of a decrease in anisotropy from the tendon to the bone. We provided elemental maps across the fibrocartilage for its organic and inorganic constituents through time-of-flight secondary ion mass spectrometry (TOF-SIMS). The apatite intensity distribution from the tendon to bone was shown to follow a linear trend, supporting past results based on Raman microprobe analysis. The merit of this study lies in the image-based simplified approach to fiber distribution quantification and in the high spatial resolution of the compositional analysis. In conjunction with the mechanical properties of the insertion tissue, fiber, and mineral distribution results for the insertion from this may potentially be incorporated into the development of a structural constitutive approach toward computational modeling. Characterizing the properties of the native insertion tissue would provide the

  6. Refixation of the supraspinatus tendon in a rat model—influence of continuous growth factor application on tendon structure

    National Research Council Canada - National Science Library

    Buchmann, Stefan; Sandmann, Gunther H; Walz, Lars; Hoppe, Henriette; Beitzel, Knut; Wexel, Gabriele; Tian, Weiwei; Winter, Gerhard; Imhoff, Andreas B

    2013-01-01

    The purpose was to evaluate histological changes of the supraspinatus tendon (SSP) after refixation under continuous growth factor application over 20 days in comparison to the native healing process...

  7. Achilles tendon structure improves on UTC imaging over a 5-month pre-season in elite Australian football players.

    Science.gov (United States)

    Docking, S I; Rosengarten, S D; Cook, J

    2016-05-01

    Pre-season injuries are common and may be due to a reintroduction of training loads. Tendons are sensitive to changes in load, making them vulnerable to injury in the pre-season. This study investigated changes in Achilles tendon structure on ultrasound tissue characterization (UTC) over the course of a 5-month pre-season in elite male Australian football players. Eighteen elite male Australian football players with no history of Achilles tendinopathy and normal Achilles tendons were recruited. The left Achilles tendon was scanned with UTC to quantify the stability of the echopattern. Participants were scanned at the start and completion of a 5-month pre-season. Fifteen players remained asymptomatic over the course of the pre-season. All four echo-types were significantly different at the end of the pre-season, with the overall echopattern suggesting an improvement in Achilles tendon structure. Three of the 18 participants developed Achilles tendon pain that coincided with a change in the UTC echopattern. This study demonstrates that the UTC echopattern of the Achilles tendon improves over a 5-month pre-season training period, representing increased fibrillar alignment. However, further investigation is needed to elucidate with this alteration in the UTC echopattern results in improved tendon resilience and load capacity. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Effect of habitual exercise on the structural and mechanical properties of human tendon, in vivo, in men and women.

    Science.gov (United States)

    Westh, E; Kongsgaard, M; Bojsen-Moller, J; Aagaard, P; Hansen, M; Kjaer, M; Magnusson, S P

    2008-02-01

    We examined whether long-term habitual training (a) was associated with differences in structural and mechanical properties in tendon in women and (b) yielded different tendon properties in men and women. Ten male runners, 10 female runners and 10 female non-runners were tested. Tendon cross-sectional area (CSA) and length of the patellar and Achilles tendon were determined with MRI. Ultrasonography-based measurement of tendon elongation and force during isometric contractions provided mechanical properties. Distal patellar and Achilles tendon CSAs were greater than the proximal part in all three groups (Puntrained women (2.60+/-0.13 mm(2)/kg(3/4)), while that in trained men (3.77+/-0.27 mm(2)/kg(3/4)) was greater compared with trained women (Puntrained women, while that in trained men was greater compared with trained women (Prunners (3528+/-773 N/mm) compared with female runners (2069+/-666 N/mm) and non-runners (2477+/-381 N/mm), (P<0.01), but patellar tendon deformation, stress, strain and modulus were similar. These data indirectly suggest that the ability of Achilles and patellar tendons to adapt in response to habitual loading such as running is attenuated in women.

  9. The influence of physical activity during youth on structural and functional properties of the Achilles tendon

    DEFF Research Database (Denmark)

    Lenskjold, A; Kongsgaard, M; Larsen, J O

    2015-01-01

    were either physically active (HAY) or inactive (LAY) in young age. Twelve men in HAY group and eight men in LAY group participated. Structural, functional, and biochemical properties of Achilles tendon were estimated from magnetic resonance imaging, ultrasound video recordings, mechanical tests......-link density did not differ between the groups, nor did collagen fibril density, diameter, and area. There was a correlation between age and pentosidine/collagen within the groups [(HAY: P activity during youth...

  10. Structural and Ultrastructural Characteristics of Bone-Tendon Junction of the Calcaneal Tendon of Adult and Elderly Wistar Rats.

    Directory of Open Access Journals (Sweden)

    Diego Pulzatto Cury

    Full Text Available Tendons are transition tissues that transfer the contractile forces generated by the muscles to the bones, allowing movement. The region where the tendon attaches to the bone is called bone-tendon junction or enthesis and may be classified as fibrous or fibrocartilaginous. This study aims to analyze the collagen fibers and the cells present in the bone-tendon junction using light microscopy and ultrastructural techniques as scanning electron microscopy and transmission electron microscopy. Forty male Wistar rats were used in the experiment, being 20 adult rats at 4 months-old and 20 elderly rats at 20 months-old. The hind limbs of the rats were removed, dissected and prepared to light microscopy, transmission electron microscopy and scanning electron microscopy. The aging process showed changes in the collagen fibrils, with a predominance of type III fibers in the elderly group, in addition to a decrease in the amount of the fibrocartilage cells, fewer and shorter cytoplasmic processes and a decreased synthetic capacity due to degradation of the organelles involved in synthesis.

  11. FIBRILLINS IN TENDON

    Directory of Open Access Journals (Sweden)

    Betti Giusti

    2016-10-01

    Full Text Available Tendons among connective tissue, mainly collagen, contain also elastic fibres made of fibrillin 1, fibrillin 2 and elastin that are broadly distributed in tendons and represent 1-2% of the dried mass of the tendon. Only in the last years, studies on structure and function of elastic fibres in tendons have been performed. Aim of this review is to revise data on the organization of elastic fibres in tendons, in particular fibrillin structure and function, and on the clinical manifestations associated to alterations of elastic fibres in tendons. Indeed, microfibrils may contribute to tendon mechanics; therefore, their alterations may cause joint hypermobility and contractures which have been found to be clinical features in patients with Marfan syndrome and Beals syndrome. The two diseases are caused by mutations in genes FBN1 and FBN2 encoding fibrillin 1 and fibrillin 2, respectively.

  12. New Imaging Methods for Non-invasive Assessment of Mechanical, Structural, and Biochemical Properties of Human Achilles Tendon: A Mini Review

    Science.gov (United States)

    Fouré, Alexandre

    2016-01-01

    The mechanical properties of tendon play a fundamental role to passively transmit forces from muscle to bone, withstand sudden stretches, and act as a mechanical buffer allowing the muscle to work more efficiently. The use of non-invasive imaging methods for the assessment of human tendon's mechanical, structural, and biochemical properties in vivo is relatively young in sports medicine, clinical practice, and basic science. Non-invasive assessment of the tendon properties may enhance the diagnosis of tendon injury and the characterization of recovery treatments. While ultrasonographic imaging is the most popular tool to assess the tendon's structural and indirectly, mechanical properties, ultrasonographic elastography, and ultra-high field magnetic resonance imaging (UHF MRI) have recently emerged as potentially powerful techniques to explore tendon tissues. This paper highlights some methodological cautions associated with conventional ultrasonography and perspectives for in vivo human Achilles tendon assessment using ultrasonographic elastography and UHF MRI. PMID:27512376

  13. Achilles Tendonitis

    Science.gov (United States)

    ... You Treat Achilles Tendonitis? en español Tendinitis de Aquiles Kim didn't do much over the summer ... Achilles Tendonitis and Who Gets It? Your Achilles tendon is located at the back of your foot, ...

  14. Structure of the Achilles tendon at the insertion on the calcaneal tuberosity.

    Science.gov (United States)

    Edama, Mutsuaki; Kubo, Masayoshi; Onishi, Hideaki; Takabayashi, Tomoya; Yokoyama, Erika; Inai, Takuma; Watanabe, Hiroshi; Nashimoto, Satoshi; Kageyama, Ikuo

    2016-11-01

    Findings on the twisting structure and insertional location of the AT on the calcaneal tuberosity are inconsistent. Therefore, to obtain a better understanding of the mechanisms underlying insertional Achilles tendinopathy, clarification of the anatomy of the twisting structure and location of the AT insertion onto the calcaneal tuberosity is important. The purpose of this study was to reveal the twisted structure of the AT and the location of its insertion onto the calcaneal tuberosity using Japanese cadavers. The study was conducted using 132 legs from 74 cadavers (mean age at death, 78.3 ± 11.1 years; 87 sides from men, 45 from women). Only soleus (Sol) attached to the deep layer of the calcaneal tuberosity was classified as least twist (Type I), both the lateral head of the gastrocnemius (LG) and Sol attached to the deep layer of the calcaneal tuberosity were classified as moderate twist (Type II), and only LG attached to the deep layer of the calcaneal tuberosity was classified as extreme twist (Type III). The Achilles tendon insertion onto the calcaneal tuberosity was classified as a superior, middle or inferior facet. Twist structure was Type I (least) in 31 legs (24%), Type II (moderate) in 87 legs (67%), and Type III (extreme) in 12 legs (9%). A comparison between males and females revealed that among men, 20 legs (24%) were Type I, 57 legs (67%) Type II, and eight legs (9%) Type III. Among women, 11 legs (24%) were Type I, 30 legs (67%) Type II, and four legs (9%) Type III. No significant differences were apparent between sexes. The fascicles of the Achilles tendon attach mainly in the middle facet. Anterior fibers of the Achilles tendon, where insertional Achilles tendinopathy is most likely, are Sol in Type I, LG and Sol in Type II, and LG only in Type III. This suggests the possibility that a different strain is produced in the anterior fibers of the Achilles tendon (calcaneal side) where insertional Achilles tendinopathy is most likely to occur in

  15. Structural Sizing Methodology for the Tendon-Actuated Lightweight In-Space MANipulator (TALISMAN) System

    Science.gov (United States)

    Jones, Thomas C.; Dorsey, John T.; Doggett, William R.

    2015-01-01

    The Tendon-Actuated Lightweight In-Space MANipulator (TALISMAN) is a versatile long-reach robotic manipulator that is currently being tested at NASA Langley Research Center. TALISMAN is designed to be highly mass-efficient and multi-mission capable, with applications including asteroid retrieval and manipulation, in-space servicing, and astronaut and payload positioning. The manipulator uses a modular, periodic, tension-compression design that lends itself well to analytical modeling. Given the versatility of application for TALISMAN, a structural sizing methodology was developed that could rapidly assess mass and configuration sensitivities for any specified operating work space, applied loads and mission requirements. This methodology allows the systematic sizing of the key structural members of TALISMAN, which include the truss arm links, the spreaders and the tension elements. This paper summarizes the detailed analytical derivations and methodology that support the structural sizing approach and provides results from some recent TALISMAN designs developed for current and proposed mission architectures.

  16. Tendon and ligament imaging

    Science.gov (United States)

    Hodgson, R J; O'Connor, P J; Grainger, A J

    2012-01-01

    MRI and ultrasound are now widely used for the assessment of tendon and ligament abnormalities. Healthy tendons and ligaments contain high levels of collagen with a structured orientation, which gives rise to their characteristic normal imaging appearances as well as causing particular imaging artefacts. Changes to ligaments and tendons as a result of disease and injury can be demonstrated using both ultrasound and MRI. These have been validated against surgical and histological findings. Novel imaging techniques are being developed that may improve the ability of MRI and ultrasound to assess tendon and ligament disease. PMID:22553301

  17. New imaging methods for non-invasive assessment of mechanical, structural and biochemical properties of Human Achilles tendon: a mini review

    Directory of Open Access Journals (Sweden)

    Alexandre Fouré

    2016-07-01

    Full Text Available The mechanical properties of tendon play a fundamental role to passively transmit forces from muscle to bone, withstand sudden stretches and act as a mechanical buffer allowing the muscle to work more efficiently. The use of non-invasive imaging methods for the assessment of human tendon’s mechanical, structural and biochemical properties in vivo is relatively young in sports medicine, clinical practice and basic science. Non-invasive assessment of the tendon properties may enhance the diagnosis of tendon injury and the characterization of recovery treatments. While ultrasonographic imaging is the most popular tool to assess the tendon’s structural and, indirectly, mechanical properties, ultrasonographic elastography and ultra-high field magnetic resonance imaging (UHF MRI have recently emerged as potentially powerful techniques to explore tendon tissues. This paper highlights some methodological cautions associated with conventional ultrasonography and perspectives for in vivo human Achilles tendon assessment using ultrasonographic elastography and UHF MRI.

  18. Does aerobic exercise training promote changes in structural and biomechanical properties of the tendons in experimental animals? A systematic review.

    Science.gov (United States)

    Bezerra, M A; Lemos, A; Lira, K D S; Silveira, P V C; Coutinho, M P G; E Moraes, S R A

    2012-12-01

    To develop a systematic review to evaluate, through the best scientific evidence available, the effectiveness of aerobic exercise in improving the biomechanical characteristics of tendons in experimental animals. Two independent assessors conducted a systematic search in the databases Medline/PUBMED and Lilacs/BIREME, using the following descriptors of Mesh in animal models. The ultimate load of traction and the elastic modulus tendon were used as primary outcomes and transverse section area, ultimate stress and tendon strain as secondary outcomes. The assessment of risk of bias in the studies was carried out using the following methodological components: light/dark cycle, temperature, nutrition, housing, research undertaken in conjunction with an ethics committee, randomization, adaptation of the animals to the training and preparation for the mechanical test. Eight studies, comprising 384 animals, were selected; it was not possible to combine them into one meta-analysis due to the heterogeneity of the samples. There was a trend to increasing ultimate load without changes in the other outcomes studied. Only one study met more than 80% of the quality criteria. Physical training performed in a structured way with imposition of overloads seems to be able to promote changes in tendon structure of experimental models by increasing the ultimate load supported. However, the results of the influence of exercise on the elastic modulus parameters, strain, transverse section area and ultimate stress, remain controversial and inconclusive. Such a conclusion must be evaluated with reservation as there was low methodological control in the studies included in this review.

  19. From mechanical loading to collagen synthesis, structural changes and function in human tendon

    DEFF Research Database (Denmark)

    Kjær, Michael; Langberg, Henning; Heinemeier, Katja

    2009-01-01

    a similar response whether the tendon was stimulated by concentric, isometric or eccentric muscle contraction, suggesting that strain rather that stress/torque determines the collagen-synthesis stimulating response seen with exercise. The adaptation time to chronic loading is longer in tendon tissue...... of TGF-beta, PGE2, IGF-I plus its binding proteins and interleukin-6 takes place after exercise. The increase in IGF-I expression in tendon includes the isoform that has so far been thought only to exist in skeletal muscle (mechano growth factor). The increase in IGF-I and procollagen expression showed...... compared with contractile elements of skeletal muscle or the heart, and only with very prolonged loading are significant changes in gross dimensions of the tendon observed, suggesting that habitual loading is associated with a robust change in the size and mechanical properties of human tendons...

  20. Tendon Injuries

    Science.gov (United States)

    ... What OT Can Do: Video For Professionals Ethics Tendon Injuries When a person experiences a tendon injury in the hand that affects the ability ... plan. What can a person with a hand tendon injury do? Implement a home exercise program recommended ...

  1. [Posterior tibial tendon dysfunction: what other structures are involved in the development of acquired adult flat foot?].

    Science.gov (United States)

    Herráiz Hidalgo, L; Carrascoso Arranz, J; Recio Rodríguez, M; Jiménez de la Peña, M; Cano Alonso, R; Álvarez Moreno, E; Martínez de Vega Fernández, V

    2014-01-01

    To evaluate the association of posterior tibial tendon dysfunction and lesions of diverse ankle structures diagnosed at MRI with radiologic signs of flat foot. We retrospectively compared 29 patients that had posterior tibial tendon dysfunction (all 29 studied with MRI and 21 also studied with weight-bearing plain-film X-rays) with a control group of 28 patients randomly selected from among all patients who underwent MRI and weight-bearing plain-film X-rays for other ankle problems. In the MRI studies, we analyzed whether a calcaneal spur, talar beak, plantar fasciitis, calcaneal bone edema, Achilles' tendinopathy, spring ligament injury, tarsal sinus disease, and tarsal coalition were present. In the weight-bearing plain-film X-rays, we analyzed the angle of Costa-Bertani and radiologic signs of flat foot. To analyze the differences between groups, we used Fisher's exact test for the MRI findings and for the presence of flat foot and analysis of variance for the angle of Costa-Bertani. Calcaneal spurs, talar beaks, tarsal sinus disease, and spring ligament injury were significantly more common in the group with posterior tibial tendon dysfunction (P<.05). Radiologic signs of flat foot and anomalous values for the angle of Costa-Bertani were also significantly more common in the group with posterior tibial tendon dysfunction (P<.001). We corroborate the association between posterior tibial tendon dysfunction and lesions to the structures analyzed and radiologic signs of flat foot. Knowledge of this association can be useful in reaching an accurate diagnosis. Copyright © 2011 SERAM. Published by Elsevier Espana. All rights reserved.

  2. How Obesity Affects Tendons?

    Science.gov (United States)

    Abate, Michele; Salini, Vincenzo; Andia, Isabel

    Several epidemiological and clinical observations have definitely demonstrated that obesity has harmful effects on tendons. The pathogenesis of tendon damage is multi-factorial. In addition to overload, attributable to the increased body weight, which significantly affects load-bearing tendons, systemic factors play a relevant role. Several bioactive peptides (chemerin, leptin, adiponectin and others) are released by adipocytes, and influence tendon structure by means of negative activities on mesenchymal cells. The ensuing systemic state of chronic, sub-clinic, low-grade inflammation can damage tendon structure. Metabolic disorders (diabetes, impaired glucose tolerance, and dislipidemia), frequently associated with visceral adiposity, are concurrent pathogenetic factors. Indeed, high glucose levels increase the formation of Advanced Glycation End-products, which in turn form stable covalent cross-links within collagen fibers, modifying their structure and functionality.Sport activities, so useful for preventing important cardiovascular complications, may be detrimental for tendons if they are submitted to intense acute or chronic overload. Therefore, two caution rules are mandatory: first, to engage in personalized soft training program, and secondly to follow regular check-up for tendon pathology.

  3. On the fail-safe design of tendon-driven manipulators with redundant tendons

    Energy Technology Data Exchange (ETDEWEB)

    Sheu, Jinn Biau; Liu, Tyng; Lee, Jyh Jone [National Taiwan University, Taipei (China)

    2012-06-15

    A tendon-driven manipulator having redundant tendons may possess more flexibility in operation, such as optimizing the performance of tendons, reducing the burden of each tendon, and providing fail-safe features. The purpose of this paper is to investigate the design of tendon-driven manipulators with a fail-safe feature, that is, to synthesize a system that may still remain controllable as any of the tendons have broken down or malfunctioned. Characteristics of tendon-driven manipulators are briefly discussed. Criteria for tendon-driven manipulators with redundant tendons and fail-safe feature are then established. Subsequently, constraints for such system are derived from the structure of tendon-driven manipulator. Associated with the criteria, manipulators can remain controllable when any of the tendons fails to function. Finally, a geometric method for determining the structure is developed. Examples of two-DOF and three-DOF tendondriven manipulators are demonstrated.

  4. Structural Evolution of Nonoperatively Treated High-Grade Partial-Thickness Tears of the Supraspinatus Tendon.

    Science.gov (United States)

    Kong, Bong Young; Cho, Minjoon; Lee, Hwa Ryeong; Choi, Young Eun; Kim, Sae Hoon

    2018-01-01

    High-grade partial-thickness rotator cuff tears (hPTRCTs) are frequently encountered in the shoulder. However, little information is available on the prevalence or timing of tear progression. Purpose/Hypothesis: The purpose was to prospectively evaluate the structural progression of hPTRCTs with a minimum follow-up of 1 year using magnetic resonance imaging (MRI). The hypothesis was that a substantial portion of hPTRCT patients would experience tear progression or evolution to a full-thickness rotator cuff tear. Case series; Level of evidence, 4. Between May 2010 and December 2015, 362 patients were diagnosed with hPTRCT (tear involvement >50% of the mediolateral length of the footprint) of the supraspinatus and were treated nonoperatively. Among these patients, 81 underwent follow-up MRI at least 1 year after initial presentation, and these patients were included in the final analysis. Initial and follow-up MRIs were used to determine whether tears had improved, had not changed, or had progressed. A change in tear involvement of >20% was defined as a significant change. Patients were categorized as follows: (1) a decrease in tear involvement of >20% (improved), (2) an increase or decrease of ≤20% (no change), or (3) an increase in tear involvement of >20% (progressed). Demographic data and morphologic data were analyzed to identify variables related to tear progression. Among them, severity of tendinosis was graded using MRIs: grade 1 (mild tendinosis), mild focal increase in tendon signal; grade 2 (moderate tendinosis), moderate focal increase in tendon signal; and grade 3 (marked tendinosis), marked generalized increase in tendon signal. At initial diagnosis, 23 were articular-side (28%) and 58 were bursal-side (72%) hPTRCTs. The study cohort was composed of 51 women and 30 men, and the mean patient age was 62.3 years (range, 41-77 years). Follow-up MRI was performed at a mean 19.9 ± 10.9 months (range, 12-52 months). A significant change in tear involvement

  5. Novel application of Theranekron® enhanced the structural and functional performance of the tenotomized tendon in rabbits.

    Science.gov (United States)

    Oryan, Ahmad; Moshiri, Ali; Raayat, Ali Reza

    2012-01-01

    The effects of Tarantula cubensis extract (TC; Theranekron®) on the experimentally induced rupture of the superficial digital flexor tendon (SDFT) 28 days post-injury (DPI) was studied in rabbits. Forty mature White New Zealand male rabbits were randomly divided into two groups. TC was repeatedly injected subcutaneously over the lesion 3, 7 and 10 days after tenotomy and surgical anastomosis. Clinical and ultrasonographic evaluations were conducted at weekly intervals. The animals were euthanized 28 DPI and the tendons were investigated for macroscopic, histopathologic, ultrastructural, biomechanical and percent dry weight parameters. Treatment reduced signs of acute inflammation and strongly ameliorated clinical symptoms, structural organization and biomechanical properties (p < 0.05). Apparently, TC is effective in restoring the clinical, morphological and biomechanical properties of the injured SDFT in rabbits and may be valuable in human and veterinary medicine. Copyright © 2012 S. Karger AG, Basel.

  6. DOES AEROBIC EXERCISE TRAINING PROMOTE CHANGES IN STRUCTURAL AND BIOMECHANICAL PROPERTIES OF THE TENDONS IN EXPERIMENTAL ANIMALS? A SYSTEMATIC REVIEW

    Directory of Open Access Journals (Sweden)

    Márcio A. Bezerra

    2012-11-01

    Full Text Available To develop a systematic review to evaluate, through the best scientific evidence available, the effectiveness of aerobic exercise in improving the biomechanical characteristics of tendons in experimental animals. Two independent assessors conducted a systematic search in the databases Medline/PUBMED and Lilacs/BIREME, using the following descriptors of Mesh in animal models. The ultimate load of traction and the elastic modulus tendon were used as primary outcomes and transverse section area, ultimate stress and tendon strain as secondary outcomes. The assessment of risk of bias in the studies was carried out using the following methodological components: light/dark cycle, temperature, nutrition, housing, research undertaken in conjunction with an ethics committee, randomization, adaptation of the animals to the training and preparation for the mechanical test. Eight studies, comprising 384 animals, were selected; it was not possible to combine them into one meta-analysis due to the heterogeneity of the samples. There was a trend to increasing ultimate load without changes in the other outcomes studied. Only one study met more than 80% of the quality criteria. Physical training performed in a structured way with imposition of overloads seems to be able to promote changes in tendon structure of experimental models by increasing the ultimate load supported. However, the results of the influence of exercise on the elastic modulus parameters, strain, transverse section area and ultimate stress, remain controversial and inconclusive. Such a conclusion must be evaluated with reservation as there was low methodological control in the studies included in this review.

  7. Computed Tomography Assessment of Peroneal Tendon Displacement and Posteromedial Structure Entrapment in Pilon Fractures.

    Science.gov (United States)

    Fokin, Alex; Huntley, Samuel R; Summers, Spencer H; Lawrie, Charles M; Miranda, Alejandro D; Caban-Martinez, Alberto J; Steinlauf, Steven D

    2016-11-01

    To determine the proportion of (1) peroneal tendon displacement (PTD) and posteromedial structure entrapment (PMSE) cases in a sample of pilon fractures, (2) missed diagnoses of PTD and PMSE on computed tomography (CT) by radiologists and attending orthopaedic trauma surgeons, and PTD and PMSE cases by (3) OTA/AO classification, and (4) fibular fracture. Retrospective cohort review. Regional level 1 Trauma Center. Two hundred patients treated between July 2008 and November 2014. Axial and reconstructed CT images were used in bone and soft tissue windows to identify PTD and PMSE. Medical charts were reviewed to identify OTA/AO fracture classification, the presence of concomitant fibular fracture, whether radiologist CT interpretation noted PTD or PMSE, and whether attending orthopaedic trauma surgeons' operative notes mentioned recognition of and management of PTD or PMSE. From the retrospective review of CT, PTD was identified in 11.0% and PMSE in 19.0% of all pilon fractures. Of the 22 patients with PTD, 59.1% sustained a concomitant fibular fracture and 90.9% sustained a 43-C fracture. Patients with PTD sustained more 43-C fractures (90.9% vs. 62.9%) but significantly fewer fibular fractures (59.1% vs. 80.3%; P = 0.023) than patients without PTD. Of the 38 patients with PMSE, 81.6% sustained a fibular fracture and 86.8% sustained a 43-C fracture. PMSE was more common in patients with 43-C fractures (86.8% vs. 61.1%). The final preoperative radiologist CT interpretation commented on PTD and PMSE in 50.0% of cases. Higher energy pilon fractures (43-C) are associated with higher incidence of PMSE and PTD. Concomitant fibula fracture may play a protective role in PTD in the setting of pilon fractures. Both attending radiologists and attending orthopaedic trauma surgeons frequently fail to recognize the diagnoses of PTD and PMSE. Prognostic level III. See Instructions for Authors for a complete description of levels of evidence.

  8. MRI of the Achilles tendon

    Energy Technology Data Exchange (ETDEWEB)

    Naegele, M.; Lienemann, A.; Hahn, D.; Lissner, J.; Boehm, P.

    1987-06-01

    The Achilles tendon and preachillar space of 30 patients was studied by MRI. A surface coil (Helmholtz' principle) was applied and all patients were examined with a superconducting magnet operating at 1.0 Tesla field strength. The purpose of the study was to illustrate pathological changes of the tendon and the surrounding soft tissue. In 3 cases MRI diagnosed a total rupture of the Achilles tendon. Furthermore, the strain of the tendon and side effects of an inflammatory process could be demonstrated. The use of a surface coil yields a high resolution of the normal anatomy of the region and of the pathological changes of the tendon and the surrounding soft tissue structures. The advantages of MRI for Achilles tendon diagnostics against competitive modalities are 1) excellent soft tissue contrast, 2) multiplanar imaging, 3) as well as exact delineation and visualisation of the lesion.

  9. Effect of PNF stretching training on the properties of human muscle and tendon structures.

    Science.gov (United States)

    Konrad, A; Gad, M; Tilp, M

    2015-06-01

    The purpose of this study was to investigate the influence of a 6-week proprioceptive neuromuscular facilitation (PNF) stretching training program on the various parameters of the human gastrocnemius medialis muscle and the Achilles tendon. Therefore, 49 volunteers were randomly assigned into PNF stretching and control groups. Before and after the stretching intervention, we determined the maximum dorsiflexion range of motion (RoM) with the corresponding fascicle length and pennation angle. Passive resistive torque (PRT) and maximum voluntary contraction (MVC) of the musculo-articular complex were measured with a dynamometer. Muscle-tendon junction (MTJ) displacement allowed us to determine the length changes in tendon and muscle, and hence to calculate stiffness. Mean RoM increased from 31.1 ± 7.2° to 33.1 ± 7.2° (P = 0.02), stiffness of the tendon decreased significantly in both active (from 21.1 ± 8.0 to 18.1 ± 5.5 N/mm) and passive (from 12.1 ± 4.9 to 9.6 ± 3.2 N/mm) conditions, and the pennation angle increased from 18.5 ± 1.8° to 19.5 ± 2.1° (P = 0.01) at the neutral ankle position (90°), only in the intervention group, whereas MVC and PRT values remained unchanged. We conclude that a 6-week PNF stretching training program increases RoM and decreases tendon stiffness, despite no change in PRT. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Histopathological findings in chronic tendon disorders.

    Science.gov (United States)

    Järvinen, M; Józsa, L; Kannus, P; Järvinen, T L; Kvist, M; Leadbetter, W

    1997-04-01

    Tendon injuries and other tendon disorders represent a common diagnostic and therapeutic challenge in sports medicine, resulting in chronic and long-lasting problems. Tissue degeneration is a common finding in many sports-related tendon complaints. In the great majority of spontaneous tendon ruptures, chronic degenerative changes are seen at the rupture site of the tendon (1). Systemic diseases and diseases specifically deteriorating the normal structure of the tendon (i.e. foreign bodies, and metabolic, inherited and infectious tendon diseases) are only rarely the cause of tendon pathology. Inherited diseases, such as various hereditary diseases with disturbed collagen metabolism and characteristic pathological structural alterations (Ehlers-Danlos syndrome, Marfani syndrome, homocystinuria (ochronosis)), represent approximately 1% of the causes of chronic tendon complaints (2), whereas foreign bodies are somewhat more common and are found in less than 10% of all chronic tendon problems (1). Rheumatoid arthritis and sarcoidosis are typical systemic diseases that cause chronic inflammation in tendon and peritendinous tissues. Altogether, these 'specific' disorders represented less than 2% of the pathological alterations found in the histological analysis of more than 1000 spontaneously ruptured tendons (1, 3, 4). In this material, degenerative changes were seen in a great majority of the tendons, indicating that a spontaneous tendon rupture is a typical clinical end-state manifestation of a degenerative process in the tendon tissue. The role of overuse in the pathogenesis of chronic tendon injuries and disorders is not completely understood. It has been speculated that when tendon is overused it becomes fatigued and loses its basal reparative ability, the repetitive microtraumatic processes thus overwhelming the ability of the tendon cells to repair the fiber damage. The intensive repetitive activity, which often is eccentric by nature, may lead to cumulative

  11. Novel methods for tendon investigations

    DEFF Research Database (Denmark)

    Kjær, Michael; Langberg, Henning; Bojsen-Møller, J.

    2008-01-01

    Purpose. Tendon structures have been studied for decades, but over the last decade, methodological development and renewed interest for metabolic, circulatory and tissue protein turnover in tendon tissue has resulted in a rising amount of investigations. Method. This paper will detail the various...

  12. Basic mechanisms of tendon fatigue damage

    OpenAIRE

    Neviaser, Andrew; Andarawis-Puri, Nelly; Flatow, Evan

    2012-01-01

    Pathologic processes intrinsic and extrinsic to the tendons have been proposed as the underlying cause of rotator cuff disease, but the precise etiology is not known. Tear formation is, in part, attributable to the accumulation of subrupture tendon fatigue damage. We review the molecular, mechanical, and structural changes induced in tendons subjected to controlled amounts of fatigue loading in an animal model of early tendinopathy. The distinct tendon responses to low and moderate levels of ...

  13. Diagnostic value of tendon thickness and structure in the sonographic diagnosis of supraspinatus tendinopathy: room for a two-step approach

    Energy Technology Data Exchange (ETDEWEB)

    Arend, Carlos Frederico, E-mail: carlos_arend@hotmail.com; Arend, Ana Amalia, E-mail: ana.amalia.arend@hotmail.com; Rodrigues da Silva, Tiago, E-mail: rumoabali@hotmail.com

    2014-06-15

    Objective: The aim of our study was to systematically compare different methodologies to establish an evidence-based approach based on tendon thickness and structure for sonographic diagnosis of supraspinatus tendinopathy when compared to MRI. Methods: US was obtained from 164 symptomatic patients with supraspinatus tendinopathy detected at MRI and 42 asymptomatic controls with normal MRI. Diagnostic yield was calculated for either maximal supraspinatus tendon thickness (MSTT) and tendon structure as isolated criteria and using different combinations of parallel and sequential testing at US. Chi-squared tests were performed to assess sensitivity, specificity, and accuracy of different diagnostic approaches. Results: Mean MSTT was 6.68 mm in symptomatic patients and 5.61 mm in asymptomatic controls (P < .05). When used as an isolated criterion, MSTT > 6.0 mm provided best results for accuracy (93.7%) when compared to other measurements of tendon thickness. Also as an isolated criterion, abnormal tendon structure (ATS) yielded 93.2% accuracy for diagnosis. The best overall yield was obtained by both parallel and sequential testing using either MSTT > 6.0 mm or ATS as diagnostic criteria at no particular order, which provided 99.0% accuracy, 100% sensitivity, and 95.2% specificity. Among these parallel and sequential tests that provided best overall yield, additional analysis revealed that sequential testing first evaluating tendon structure required assessment of 258 criteria (vs. 261 for sequential testing first evaluating tendon thickness and 412 for parallel testing) and demanded a mean of 16.1 s to assess diagnostic criteria and reach the diagnosis (vs. 43.3 s for sequential testing first evaluating tendon thickness and 47.4 s for parallel testing). Conclusions: We found that using either MSTT > 6.0 mm or ATS as diagnostic criteria for both parallel and sequential testing provides the best overall yield for sonographic diagnosis of supraspinatus tendinopathy when

  14. The vascularization of human flexor tendons within the digital synovial sheath region--structureal and functional aspects.

    Science.gov (United States)

    Lundborg, G; Myrhage, R; Rydevik, B

    1977-11-01

    The intrinsic vascularization of human flexor tendons within the digital sheath region was studied on fresh amputation specimens with the aid of angiographic and histochemical techniques. In the flexor digitorum profundus tendon, three separate vascular systems of various origin and with no or very little communication could be verified. In the flexor digitorum superficialis tendon, two such systems were observed. The volar surface of both tendons is more or less devoid of vessels. Moreover, at the proximal interphalangeal joint level, the flexor digitorum profundus tendon has a volar avascular zone, constituting about 1 mm, i.e., about one-third to one-fourth of the thickness of the tendon. It is assumed that the synovial fluid is of importance for the nutrition of the tendons and that therefore the synovial sheath should be preserved as much as possible.

  15. Midportion Achilles tendinosis and the plantaris tendon.

    Science.gov (United States)

    Alfredson, Håkan

    2011-10-01

    When re-operating patients with midportion Achilles tendinosis, having had a poor effect of ultrasound (US) and Doppler-guided scraping, the author found the involvement of the plantaris tendon to be a likely reason for the poor result. The aim of this study was to investigate the occurrence of a plantaris tendon in close relation to the Achilles tendon in consecutive patients with midportion Achilles tendinosis undergoing treatment with US and Doppler-guided scraping. This study includes 73 consecutive tendons with chronic painful midportion Achilles tendinosis, where US+Doppler examination showed thickening, irregular tendon structure, hypo-echoic regions, and localised high blood flow outside and inside the ventral Achilles midportion. The tendons were treated with US+Doppler-guided scraping, via a medial incision. If there was a plantaris tendon located in close relation to the medial Achilles, it was extirpated. An invaginated, or 'close by located', enlarged plantaris tendon was found in 58 of 73 (80%) tendons. Preliminary clinical results of the combined procedure, US + Doppler-guided surgical scraping and extirpation of the plantaris tendon, are very promising. A thickened plantaris tendon located in close relation to the medial Achilles seems common in patients with chronic painful midportion tendinosis. The role of the plantaris tendon in midportion Achilles tendinosis needs to be further evaluated and should be kept in mind when treating this condition.

  16. Structural mechanical properties of radiation-sterilized human Bone-Tendon-Bone grafts preserved by different methods.

    Science.gov (United States)

    Gut, Grzegorz; Marowska, Joanna; Jastrzebska, Anna; Olender, Ewa; Kamiński, Artur

    2016-06-01

    To avoid the risk of infectious disease transmission from donor to recipient, allografts should be terminally sterilized. In the previous paper (Kaminski et al. in Cell Tissue Bank 10:215-219, 2009) we presented the effect of various methods of preservation (deep fresh freezing, glycerolization, lyophilization), followed by irradiation with different doses of electron beam (EB), on material (intrinsic) mechanical properties of human patellar tendons cut out as for anterior cruciate ligament reconstruction, obtained in failure tensile test. As structural mechanical properties are equally important to predict the behaviour of the graft as a whole functional unit, the purpose of the present paper was to show the results for failure load and elongation, obtained in the same experiment. Paired Bone-Tendon-Bone grafts (BTB) were prepared from cadaveric human patella tendons with both patellar and tibial attachments. They were preserved by deep freezing, glycerolization or lyophilization and subsequently EB-irradiated with the doses of 25, 35, 50 or 100 kGy (fresh-frozen grafts) or a single dose of 35 kGy (glycerolized and lyophilized grafts). Each experimental (irradiated) group was provided with control (non-irradiated), donor-matched group. The specimens from all groups were subjected to mechanical failure tensile test with the use of Instron system in order to measure their structural properties (failure load and elongation). All lyophilized grafts were rehydrated before mechanical testing. In our study we did not observe significant deterioration of structural mechanical properties of BTB grafts processed by fresh-freezing and then terminal sterilized with growing doses of EB up to 100 kGy. In contrast, BTB grafts processed by glycerolization or lyophilization and irradiated with 35 kGy showed significant decrease of failure load. Obtained results suggest that deep-frozen irradiated grafts retain their initial mechanical properties to an extent which does not

  17. [Microstructure of tendon and its clinical significance].

    Science.gov (United States)

    Yan, J G

    1990-08-01

    Superficial and internal-structure of human and rat tendons were investigated under scanning electronic microscopy. Histologically, there are many pores on the synovium, under which a layer of network of fiber bands wraps the tendon. The synovial fluid propulsion system includes: Synovium----pores----network of fiber bands----space of tendon bands----space of tendon fibers. The synovial fluid is propelled through the above structure. The function of the network structure is like a sponge, it has the function of nutrition, absorption of heat, and lubrication.

  18. Achilles Tendon Rupture

    Science.gov (United States)

    ... Achilles tendon rupture. Obesity. Excess weight puts more strain on the tendon. Prevention To reduce your chance of developing Achilles tendon problems, follow these tips: Stretch and strengthen calf muscles. Stretch your calf until you feel a noticeable ...

  19. Posterior Tibial Tendon Dysfunction

    Science.gov (United States)

    .org Posterior Tibial Tendon Dysfunction Page ( 1 ) Posterior tibial tendon dysfunction is one of the most common problems of the foot and ankle. It occurs when the posterior tibial tendon becomes inflamed or torn. As a result, the ...

  20. Achilles tendon repair

    Science.gov (United States)

    Achilles tendon rupture-surgery; Percutaneous Achilles tendon rupture repair ... To fix your torn Achilles tendon, the surgeon will: Make a cut down the back of your heel Make several small cuts rather than one large ...

  1. Quadriceps tendon allografts as an alternative to Achilles tendon allografts: a biomechanical comparison.

    Science.gov (United States)

    Mabe, Isaac; Hunter, Shawn

    2014-12-01

    Quadriceps tendon with a patellar bone block may be a viable alternative to Achilles tendon for anterior cruciate ligament reconstruction (ACL-R) if it is, at a minimum, a biomechanically equivalent graft. The objective of this study was to directly compare the biomechanical properties of quadriceps tendon and Achilles tendon allografts. Quadriceps and Achilles tendon pairs from nine research-consented donors were tested. All specimens were processed to reduce bioburden and terminally sterilized by gamma irradiation. Specimens were subjected to a three phase uniaxial tension test performed in a custom environmental chamber to maintain the specimens at a physiologic temperature (37 ± 2 °C) and misted with a 0.9 % NaCl solution. There were no statistical differences in seven of eight structural and mechanical between the two tendon types. Quadriceps tendons exhibited a significantly higher displacement at maximum load and significantly lower stiffness than Achilles tendons. The results of this study indicated a biomechanical equivalence of aseptically processed, terminally sterilized quadriceps tendon grafts with bone block to Achilles tendon grafts with bone block. The significantly higher displacement at maximum load, and lower stiffness observed for quadriceps tendons may be related to the failure mode. Achilles tendons had a higher bone avulsion rate than quadriceps tendons (86 % compared to 12 %, respectively). This was likely due to observed differences in bone block density between the two tendon types. This research supports the use of quadriceps tendon allografts in lieu of Achilles tendon allografts for ACL-R.

  2. DOES AEROBIC EXERCISE TRAINING PROMOTE CHANGES IN STRUCTURAL AND BIOMECHANICAL PROPERTIES OF THE TENDONS IN EXPERIMENTAL ANIMALS? A SYSTEMATIC REVIEW

    OpenAIRE

    Márcio A. Bezerra; Kamilla D.S. Lira; Patrícia V. C. Silveira; Marcos P.G. Coutinho; Andrea Lemos; Silvia R. A. Moraes

    2012-01-01

    To develop a systematic review to evaluate, through the best scientific evidence available, the effectiveness of aerobic exercise in improving the biomechanical characteristics of tendons in experimental animals. Two independent assessors conducted a systematic search in the databases Medline/PUBMED and Lilacs/BIREME, using the following descriptors of Mesh in animal models. The ultimate load of traction and the elastic modulus tendon were used as primary outcomes and transverse section area,...

  3. Flexor tendon nutrition.

    Science.gov (United States)

    Manske, P R; Lesker, P A

    1985-02-01

    The concepts regarding nutrient pathways to flexor tendons within the digital sheath are reviewed. Historically, both diffusion and perfusion have been considered significant pathways to the flexor tendon. Theories of tendon healing and adhesion formation, as well as techniques employed by the surgeon in the repair of tendons, are based on these concepts.

  4. The early effects of sustained platelet-derived growth factor administration on the functional and structural properties of repaired intrasynovial flexor tendons: an in vivo biomechanic study at 3 weeks in canines.

    Science.gov (United States)

    Gelberman, Richard H; Thomopoulos, Stavros; Sakiyama-Elbert, Shelly E; Das, Rosalina; Silva, Matthew J

    2007-03-01

    A bioactive fibrin-based delivery system was used to provide sustained administration of platelet-derived growth factor (PDGF-BB) in a clinically relevant model of intrasynovial flexor tendon repair. We hypothesized that PDGF-BB administered in this manner would improve the sutured tendon's functional and structural properties 3 weeks after repair. A delivery system consisting of 30 microL of fibrin matrix, peptide, heparin, and 100 ng of PDGF-BB was incorporated into the repair sites of randomly selected medial or lateral forepaw flexor digitorum profundus tendons of 8 adult mongrel dogs. The remaining forepaw flexor digitorum profundus tendons were repaired without the growth-factor and fibrin-based delivery system and served as controls. The surgically treated forelimbs were treated with controlled passive motion rehabilitation. The animals were killed at 3 weeks, at which time the tendons were tested for range of motion with a motion analysis system and for tensile properties with a materials testing machine. Proximal interphalangeal joint and distal interphalangeal joint rotation values were significantly higher for the PDGF-BB-treated tendons compared with the repair-alone tendons. Excursion values were also significantly higher in the PDGF-BB-treated tendons. There were no significant differences in tensile properties when comparing PDGF-BB-treated with repair-alone tendons. The functional properties of repaired intrasynovial flexor tendons were significantly improved with the sustained administration of PDGF-BB. The failure to achieve improvements in ultimate load, stiffness, and strain in the experimental group may have been due to suboptimal PDGF-BB dosage or suboptimal release kinetics.

  5. Tendon Force Transmission at the Nanoscale

    DEFF Research Database (Denmark)

    Svensson, René

    2013-01-01

    of connective tissue function that are poorly understood. One such aspect is the microscopic mechanisms of force transmission through tendons over macroscopic distances. Force transmission is at the heart of tendon function, but the large range of scales in the hierarchical structure of tendons has made...... it difficult to tackle. The tendon hierarchy ranges from molecules (2 nm) over fibrils (200 nm), fibers (2 μm) and fascicles (200 μm) to tendons (10 mm), and to derive the mechanisms of force transmission it is necessary to know the mechanical behavior at each hierarchical level. The aim of the present work...... was to elucidate the mechanisms of force transmission in tendons primarily by investigating the mechanical behavior at the hierarchical level of collagen fibrils. To do so we have developed an atomic force microscopy (AFM) method for tensile testing of native collagen fibrils. The thesis contains five papers...

  6. Iliopsoas Tendon Reformation after Psoas Tendon Release

    Directory of Open Access Journals (Sweden)

    K. Garala

    2013-01-01

    Full Text Available Internal snapping hip syndrome, or psoas tendonitis, is a recognised cause of nonarthritic hip pain. The majority of patients are treated conservatively; however, occasionally patients require surgical intervention. The two surgical options for iliopsoas tendinopathy are step lengthening of the iliopsoas tendon or releasing the tendon at the lesser trochanter. Although unusual, refractory snapping usually occurs soon after tenotomy. We report a case of a 47-year-old active female with internal snapping and pain following an open psoas tenotomy. Postoperatively she was symptom free for 13 years. An MRI arthrogram revealed reformation of a pseudo iliopsoas tendon reinserting into the lesser trochanter. The pain and snapping resolved after repeat iliopsoas tendon release. Reformation of tendons is an uncommon sequela of tenotomies. However the lack of long-term studies makes it difficult to calculate prevalence rates. Tendon reformation should be included in the differential diagnosis of failed tenotomy procedures after a period of symptom relief.

  7. Peroneal tendon disorders

    OpenAIRE

    Davda, Kinner; Malhotra, Karan; O'Donnell, Paul; Singh, Dishan; Cullen, Nicholas

    2017-01-01

    Pathological abnormality of the peroneal tendons is an under-appreciated source of lateral hindfoot pain and dysfunction that can be difficult to distinguish from lateral ankle ligament injuries. Enclosed within the lateral compartment of the leg, the peroneal tendons are the primary evertors of the foot and function as lateral ankle stabilisers. Pathology of the tendons falls into three broad categories: tendinitis and tenosynovitis, tendon subluxation and dislocation, and tendon splits and ...

  8. Endoscopic adhesiolysis for extensive tibialis posterior tendon and Achilles tendon adhesions following compound tendon rupture

    OpenAIRE

    Lui, Tun Hing

    2013-01-01

    Tendon adhesion is one of the most common causes of disability following tendon surgery. A case of extensive peritendinous adhesions of the Achilles tendon and tibialis posterior tendon after compound rupture of the tendons was reported. This was managed by endoscopic adhesiolysis of both tendons. The endoscopic approach allows early postoperative mobilisation which can relieve the tendon adhesion.

  9. Diseases of the tendons and tendon sheaths.

    Science.gov (United States)

    Steiner, Adrian; Anderson, David E; Desrochers, André

    2014-03-01

    Contracted flexor tendon leading to flexural deformity is a common congenital defect in cattle. Arthrogryposis is a congenital syndrome of persistent joint contracture that occurs frequently in Europe as a consequence of Schmallenberg virus infection of the dam. Spastic paresis has a hereditary component, and affected cattle should not be used for breeding purposes. The most common tendon avulsion involves the deep digital flexor tendon. Tendon disruptions may be successfully managed by tenorrhaphy and external coaptation or by external coaptation alone. Medical management alone is unlikely to be effective for purulent tenosynovitis. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Chronic alterations in growth hormone/insulin-like growth factor-I signaling lead to changes in mouse tendon structure

    DEFF Research Database (Denmark)

    Nielsen, R H; Clausen, N M; Schjerling, P

    2014-01-01

    The growth hormone/insulin-like growth factor-I (GH/IGF-I) axis is an important stimulator of collagen synthesis in connective tissue, but the effect of chronically altered GH/IGF-I levels on connective tissue of the muscle-tendon unit is not known. We studied three groups of mice; 1) giant...

  11. The effect of glucocorticoids on tendon cell viability in human tendon explants

    Science.gov (United States)

    Lui, Wai Ting; Chuen Fu, Sai; Man Lee, Kwong

    2009-01-01

    Background and purpose Previous studies on the culture of human tenocytes have shown that dexamethasone and triamcino-lone reduce cell viability, suppress cell proliferation, and reduce collagen synthesis. However, such cell cultures lack the extracellular matrix and three-dimensional structure of normal tendons, which affects their response to stimuli. We established a human tendon explant culture system and tested the effects of dexamethasone and triamcinolone on cell viability. Methods Primary human tendon explant cultures were prepared from healthy hamstring tendons. Tendon strips were harvested from hamstring tendons and cultured in 24-well plates in Dulbecco’s modification of Eagle’s Medium (DMEM) supplemented with 2% fetal calf serum. The tendon explants were treated with 0 μM (control), 10 μM, or 100 μM dexamethasone sodium phosphate or 0 μM (control), 10 μM, or 100 μM triamcinolone acetonide in DMEM for 96 h. Cell viability was measured by Alamar blue assay before and after glucocorticoid treatment. Results Incubation with 10 μM and 100 μM dexamethasone reduced cell viability in human tendon explants by 35% and 45%, respectively, as compared to a 6% increase in the controls (p = 0.01, mixed-effects ANOVA). Triamcinolone at 10 μM and 100 μM reduced cell viability by 33% and 36%, respectively, as compared to a 9% increase in the controls (p = 0.07, mixed-effects ANOVA). Interpretation Human tendon explant cultures can be used to study the effects of glucocorticoids on human tendon. Dexamethasone and triamcinolone suppress the cell viability of human tendon in its natural 3-dimensional environment with matrix anchorage. Human tendon explant cultures provide a species-specific model for further investigation of the effects of glucocorticoids on the metabolism of the extracellular matrix of human tendon, and on its mechanical properties. PMID:19421908

  12. Peroneal Tendon Injuries

    Science.gov (United States)

    ... the type of peroneal tendon injury. Options include: Immobilization. A cast or splint may be used to ... arthritis, gout, tendonitis, fracture, nerve compression (tarsal tunnel syndrome), infection and... Founded in 1942, the American College ...

  13. Chronic Achilles Tendon Rupture

    Science.gov (United States)

    Maffulli, Nicola; Via, Alessio Giai; Oliva, Francesco

    2017-01-01

    Background: The Achilles tendon, the largest and strongest tendon in the human body, is nevertheless one of the tendons which most commonly undergoes a complete subcutaneous tear. Achilles tendon ruptures are especially common in middle aged men who occasionally participate in sport. Even though Achilles tendon ruptures are frequent, up to 25% of acute injuries are misdiagnosed, and present as chronic injuries. Methods: This is a review article about diagnosis and management of chronic Achilles tendon ruptures. Minimally invasive Achilles tendon reconstruction is discussed. Results: The optimal surgical procedure is still debated, however, less invasive peroneus brevis reconstruction technique and free hamstring autograft provide good functional results. Conclusion: The management of chronic ruptures is more demanding than acute tears, because of the retraction of the tendon ends, and the gap makes primary repair impossible. Wound complications and infections are frequent after open procedures. Minimally invasive treatments provide good functional results and lower complications rate. PMID:29081863

  14. Using the zebrafish to understand tendon development and repair.

    Science.gov (United States)

    Chen, J W; Galloway, J L

    2017-01-01

    Tendons are important components of our musculoskeletal system. Injuries to these tissues are very common, resulting from occupational-related injuries, sports-related trauma, and age-related degeneration. Unfortunately, there are few treatment options, and current therapies rarely restore injured tendons to their original function. An improved understanding of the pathways regulating their development and repair would have significant impact in stimulating the formulation of regenerative-based approaches for tendon injury. The zebrafish provides an ideal system in which to perform genetic and chemical screens to identify new pathways involved in tendon biology. Until recently, there had been few descriptions of tendons and ligaments in the zebrafish and their similarity to mammalian tendon tissues. In this chapter, we describe the development of the zebrafish tendon and ligament tissues in the context of their gene expression, structure, and interactions with neighboring musculoskeletal tissues. We highlight the similarities with tendon development in higher vertebrates, showing that the craniofacial tendons and ligaments in zebrafish morphologically, molecularly, and structurally resemble mammalian tendons and ligaments from embryonic to adult stages. We detail methods for fluorescent in situ hybridization and immunohistochemistry as an assay to examine morphological changes in the zebrafish musculoskeleton. Staining assays such as these could provide the foundation for screen-based approaches to identify new regulators of tendon development, morphogenesis, and repair. These discoveries would provide new targets and pathways to study in the context of regenerative medicine-based approaches to improve tendon healing. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. MRI of normal achilles tendon

    Energy Technology Data Exchange (ETDEWEB)

    Rollandi, G.A. [Institute of Radiology, Univ. of Genoa (Italy); Bertolotto, M. [Institute of Radiology, Univ. of Genoa (Italy); Perrone, R. [Institute of Radiology, Univ. of Genoa (Italy); Garlaschi, G. [Institute of Radiology, Univ. of Genoa (Italy); Derchi, L.E. [Institute of Radiology, Univ. of Genoa (Italy)

    1995-12-01

    To investigate the normal internal structure of tendons 11 volunteers without clinical evidence of tendinopathy were examined using conventional spin-echo T1-, T2- and proton-density weighted sequences. The Achilles tendon was chosen because of its high frequency of injury in athletic activity, large size, superficial position and because it is oriented nearly parallel to the static magnetic field, therefore minimizing the ``magic angle phenomenon``. The tendons exhibited areas of slighly increased signal in four T1-weighted and in all but one proton-density-weighted scans. No intratendinous signal was detected in T2-weighted images. The possible origin of these findings is discussed. We conclude that the knowledge of these normal signals may be useful to avoid incorrectly diagnosing as pathological. (orig.). With 2 figs.

  16. Biologics for tendon repair☆

    Science.gov (United States)

    Docheva, Denitsa; Müller, Sebastian A.; Majewski, Martin; Evans, Christopher H.

    2015-01-01

    Tendon injuries are common and present a clinical challenge to orthopedic surgery mainly because these injuries often respond poorly to treatment and require prolonged rehabilitation. Therapeutic options used to repair ruptured tendons have consisted of suture, autografts, allografts, and synthetic prostheses. To date, none of these alternatives has provided a successful long-term solution, and often the restored tendons do not recover their complete strength and functionality. Unfortunately, our understanding of tendon biology lags far behind that of other musculoskeletal tissues, thus impeding the development of new treatment options for tendon conditions. Hence, in this review, after introducing the clinical significance of tendon diseases and the present understanding of tendon biology, we describe and critically assess the current strategies for enhancing tendon repair by biological means. These consist mainly of applying growth factors, stem cells, natural biomaterials and genes, alone or in combination, to the site of tendon damage. A deeper understanding of how tendon tissue and cells operate, combined with practical applications of modern molecular and cellular tools could provide the long awaited breakthrough in designing effective tendon-specific therapeutics and overall improvement of tendon disease management. PMID:25446135

  17. p38 MAPK signaling in postnatal tendon growth and remodeling.

    Directory of Open Access Journals (Sweden)

    Andrew J Schwartz

    Full Text Available Tendon is a dynamic tissue whose structure and function is influenced by mechanical loading, but little is known about the fundamental mechanisms that regulate tendon growth and remodeling in vivo. Data from cultured tendon fibroblasts indicated that the p38 MAPK pathway plays an important role in tendon fibroblast proliferation and collagen synthesis in vitro. To gain greater insight into the mechanisms of tendon growth, and explore the role of p38 MAPK signaling in this process, we tested the hypotheses that inducing plantaris tendon growth through the ablation of the synergist Achilles tendon would result in rapid expansion of a neotendon matrix surrounding the original tendon, and that treatment with the p38 MAPK inhibitor SB203580 would prevent this growth. Rats were treated with vehicle or SB203580, and subjected to synergist ablation by bilateral tenectomy of the Achilles tendon. Changes in histological and biochemical properties of plantaris tendons were analyzed 3, 7, or 28 days after overload, and comparisons were made to non-overloaded animals. By 28 days after overload, tendon mass had increased by 30% compared to non-overloaded samples, and cross-sectional area (CSA increased by around 50%, with most of the change occurring in the neotendon. The expansion in CSA initially occurred through the synthesis of a hyaluronic acid rich matrix that was progressively replaced with mature collagen. Pericytes were present in areas of active tendon growth, but never in the original tendon ECM. Inhibition of p38 MAPK resulted in a profound decrease in IL6 expression, and had a modest effect on the expression of other ECM and cell proliferation genes, but had a negligible impact on overall tendon growth. The combined results from this study provided novel insights into tendon mechanobiology, and suggest that p38 MAPK signaling does not appear to be necessary for tendon growth in vivo.

  18. Anatomic, Vascular, and Mechanical Overview of the Achilles Tendon.

    Science.gov (United States)

    Dayton, Paul

    2017-04-01

    The Achilles tendon is the strongest and thickest tendon in the body and is subjected to unique forces during the activities of living. A variety of pathologic processes have been identified causing clinical symptoms in patients of all ages. A detailed understanding of Achilles anatomy is necessary to understand the pathologic process that are seen in the tendon. As with all medical topics and conditions, our understanding is evolving as new research sheds light on pathologic processes involved with the Achilles tendon. This article reviews the anatomic, histologic, hemodynamic, and mechanical properties of the Achilles tendon and associated muscle structures. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Multi-Layer Electrospun Membrane Mimicking Tendon Sheath for Prevention of Tendon Adhesions

    Directory of Open Access Journals (Sweden)

    Shichao Jiang

    2015-03-01

    Full Text Available Defect of the tendon sheath after tendon injury is a main reason for tendon adhesions, but it is a daunting challenge for the biomimetic substitute of the tendon sheath after injury due to its multi-layer membrane-like structure and complex biologic functions. In this study, a multi-layer membrane with celecoxib-loaded poly(l-lactic acid-polyethylene glycol (PELA electrospun fibrous membrane as the outer layer, hyaluronic acid (HA gel as middle layer, and PELA electrospun fibrous membrane as the inner layer was designed. The anti-adhesion efficacy of this multi-layer membrane was compared with a single-layer use in rabbit flexor digitorum profundus tendon model. The surface morphology showed that both PELA fibers and celecoxib-loaded PELA fibers in multi-layer membrane were uniform in size, randomly arrayed, very porous, and smooth without beads. Multi-layer membrane group had fewer peritendinous adhesions and better gliding than the PELA membrane group and control group in gross and histological observation. The similar mechanical characteristic and collagen expression of tendon repair site in the three groups indicated that the multi-layer membrane did not impair tendon healing. Taken together, our results demonstrated that such a biomimetic multi-layer sheath could be used as a potential strategy in clinics for promoting tendon gliding and preventing adhesion without poor tendon healing.

  20. Tendon functional extracellular matrix.

    Science.gov (United States)

    Screen, Hazel R C; Berk, David E; Kadler, Karl E; Ramirez, Francesco; Young, Marian F

    2015-06-01

    This article is one of a series, summarizing views expressed at the Orthopaedic Research Society New Frontiers in Tendon Research Conference. This particular article reviews the three workshops held under the "Functional Extracellular Matrix" stream. The workshops focused on the roles of the tendon extracellular matrix, such as performing the mechanical functions of tendon, creating the local cell environment, and providing cellular cues. Tendon is a complex network of matrix and cells, and its biological functions are influenced by widely varying extrinsic and intrinsic factors such as age, nutrition, exercise levels, and biomechanics. Consequently, tendon adapts dynamically during development, aging, and injury. The workshop discussions identified research directions associated with understanding cell-matrix interactions to be of prime importance for developing novel strategies to target tendon healing or repair. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  1. Hamstring tendons insertion - an anatomical study

    Directory of Open Access Journals (Sweden)

    Cristiano Antonio Grassi

    2013-09-01

    Full Text Available OBJECTIVE: To study the anatomy of the hamstring tendons insertion and anatomical rela-tionships. METHODS: Ten cadaver knees with medial and anterior intact structures were selected. The dissection was performed from anteromedial access to exposure of the insertion of the flexor tendons (FT, tibial plateau (TP and tibial tuberosity (TT. A needle of 40 × 12 and a caliper were used to measure the distance of the tibial plateau of the knee flexor tendons insertion at 15 mm from the medial border of the patellar tendon and tibial tuberosity to the insertion of the flexor tendons of the knee. The angle between tibial plateau and the insertion of the flexor tendons of the knee (A-TP-FT was calculated using Image Pro Plus software. RESULTS: The mean distance TP-FT was 41 ± 4.6 mm. The distance between the TT-FT was 6.88 ± 1 mm. The (A-TP-FT was 20.3 ± 4.9°. CONCLUSION: In the anterior tibial flexor tendons are about 40 mm from the plateau with an average of 20°.

  2. Tendon biomechanics and mechanobiology - a mini-review of basic concepts and recent advancements

    Science.gov (United States)

    Wang, James H-C.; Guo, Qianping; Li, Bin

    2011-01-01

    Due to their unique hierarchical structure and composition, tendons possess characteristic biomechanical properties, including high mechanical strength and viscoelasticity, which enable them to carry and transmit mechanical loads (muscular forces) effectively. Tendons are also mechano-responsive by adaptively changing their structure and function in response to altered mechanical loading conditions. In general, mechanical loading at physiological levels is beneficial to tendons, but excessive loading or disuse of tendons is detrimental. This mechano-adaptability is due to the cells present in tendons. Tendon fibroblasts (tenocytes) are the dominant tendon cells responsible for tendon homeostasis and repair. Tendon stem cells (TSCs), which were recently discovered, also play a vital role in tendon maintenance and repair by virtue of their ability to self-renew and differentiate into tenocytes. TSCs may also be responsible for chronic tendon injury, or tendinopathy, by undergoing aberrant differentiation into non-tenocytes in response to excessive mechanical loading. Thus, it is necessary to devise optimal rehabilitation protocols in order to enhance tendon healing while reducing scar tissue formation and tendon adhesions. Moreover, along with scaffolds that can mimic tendon matrix environments and platelet-rich plasma (PRP), which serves as a source of growth factors, TSCs may be the optimal cell type for enhancing repair of injured tendons. PMID:21925835

  3. Turkey model for flexor tendon research: in vitro comparison of human, canine, turkey, and chicken tendons.

    Science.gov (United States)

    Kadar, Assaf; Thoreson, Andrew R; Reisdorf, Ramona L; Amadio, Peter C; Moran, Steven L; Zhao, Chunfeng

    2017-08-01

    Flexor tendon injuries are one of the most common hand injuries and remain clinically challenging for functional restoration. Canine and chicken have been the most commonly used animal models for flexor tendon-related research but possess several disadvantages. The purpose of this study was to explore a potential turkey model for flexor tendon research. The third digit from human cadaveric hands, canine forepaws, turkey foot, and chicken foot were used for this study. Six digits in each of four species were studied in detail, comparing anatomy of the flexor apparatus, joint range of motioņ tendon excursion, tendon cross-sectional area, work of flexion, gliding resistance at the level of the A2 pulley, modulus of elasticity, suture retention strength, and histology across species. Anatomically, the third digit in the four species displayed structural similarities; however, the tendon cross-sectional area of the turkey and human were similar and larger than canine and chicken. Furthermore, the turkey digit resembles the human's finger with the lack of webbing between digits, similar vascularization, tendon excursion, work of flexion, gliding resistance, mechanical properties, and suture holding strength. More importantly, human and turkey tendons were most similar in histological appearance. Turkey flexor tendons have many properties that are comparable to human flexor tendons which would provide a clinically relevant, economical, nonhuman companion large animal model for flexor tendon research. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Percutaneous Achilles Tendon Lengthening

    Science.gov (United States)

    ... Ligament Reconstruction Lateral Ankle Stabilization Mosaicplasty for Osteochondral Lesions of the Talus Peroneus Longus to Achilles Tendon Transfer Pilon Fracture Surgery Posterior Ankle Endoscopy or ...

  5. Three-dimensional muscle-tendon geometry after rectus femoris tendon transfer.

    Science.gov (United States)

    Asakawa, Deanna S; Blemker, Silvia S; Rab, George T; Bagley, Anita; Delp, Scott L

    2004-02-01

    Rectus femoris tendon transfer is performed in patients with cerebral palsy to improve knee flexion during walking. This procedure involves detachment of the muscle from its insertion into the quadriceps tendon and reattachment to one of the knee flexor muscles. The purpose of the present study was to evaluate the muscle-tendon geometry and to assess the formation of scar tissue between the rectus femoris and adjacent structures. Magnetic resonance images of the lower extremities were acquired from five subjects after bilateral rectus femoris tendon transfer. A three-dimensional computer model of the musculoskeletal geometry of each of the ten limbs was created from these images. The three-dimensional paths of the rectus femoris muscles after transfer demonstrated that the muscle does not follow a straight course from its origin to its new insertion. The typical muscle-tendon path included an angular deviation; this deviation was sharp (>35 degrees ) in seven extremities. In addition, scar tissue between the transferred rectus femoris and the underlying muscles was visible on the magnetic resonance images. The angular deviations in the rectus femoris muscle-tendon path and the presence of scar tissue between the rectus femoris and the underlying muscles suggest that the beneficial effects of rectus femoris tendon transfer are derived from reducing the effects of the rectus femoris muscle as a knee extensor rather than from converting the muscle to a knee flexor. These findings clarify our understanding of the mechanism by which rectus femoris tendon transfer improves knee flexion.

  6. Tendon lengthening and transfer.

    Science.gov (United States)

    Fitoussi, F; Bachy, M

    2015-02-01

    Tendon lengthening and transfer are usually indicated for certain neuromuscular disorders, peripheral or central nerve injury, congenital disorder or direct traumatic or degenerative musculotendinous lesion. In musculotendinous lengthening, technique depends on muscle anatomy, degree of correction required, and the need to avoid excessive loss of force. Lengthening within the muscle or aponeurosis is stable. In the tendon, however, it may provide greater gain but is not stable and requires postoperative immobilization to avoid excessive lengthening. Tendon transfer consists in displacing a muscle's tendon insertion in order to restore function. The muscle to be transferred is chosen according to strength, architecture and course, contraction timing, intended direction, synergy and the joint moment arm to be restored. Functions to be restored have to be prioritized, and alternatives to transfer should be identified. The principles of tendon transfer require preoperative assessment of the quality of the tissue through which the transfer is to pass and of the suppleness of the joints concerned. During the procedure, transfer tension should be optimized and the neurovascular bundle should be protected. The method of fixation, whether tendon-to-bone or tendon-to-tendon suture, should be planned according to local conditions and the surgeon's experience. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  7. The effect of decellularized matrices on human tendon stem/progenitor cell differentiation and tendon repair.

    Science.gov (United States)

    Yin, Zi; Chen, Xiao; Zhu, Ting; Hu, Jia-jie; Song, Hai-xin; Shen, Wei-liang; Jiang, Liu-yun; Heng, Boon Chin; Ji, Jun-feng; Ouyang, Hong-Wei

    2013-12-01

    It is reported that decellularized collagen matrices derived from dermal skin and bone have been clinically used for tendon repair. However, the varying biological and physical properties of matrices originating from different tissues may influence the differentiation of tendon stem cells, which has not been systematically evaluated. In this study, the effects of collagenous matrices derived from different tissues (tendon, bone and dermis) on the cell differentiation of human tendon stem/progenitor cells (hTSPCs) were investigated, in the context of tendon repair. It was found that all three matrices supported the adhesion and proliferation of hTSPCs despite differences in topography. Interestingly, tendon-derived decellularized matrix promoted the tendinous phenotype in hTSPCs and inhibited their osteogenesis, even under osteogenic induction conditions, through modulation of the teno- and osteolineage-specific transcription factors Scleraxis and Runx2. Bone-derived decellularized matrix robustly induced osteogenic differentiation of hTSPCs, whereas dermal skin-derived collagen matrix had no apparent effect on hTSPC differentiation. Based on the specific biological function of the tendon-derived decellularized matrix, a tissue-engineered tendon comprising TSPCs and tendon-derived matrix was successfully fabricated for Achilles tendon reconstruction. Implantation of this cell-scaffold construct led to a more mature structure (histology score: 4.08 ± 0.61 vs. 8.51 ± 1.66), larger collagen fibrils (52.2 ± 1.6 nm vs. 47.5 ± 2.8 nm) and stronger mechanical properties (stiffness: 21.68 ± 7.1 Nm m(-1) vs.13.2 ± 5.9 Nm m(-1)) of repaired tendons compared to the control group. The results suggest that stem cells promote the rate of repair of Achilles tendon in the presence of a tendinous matrix. This study thus highlights the potential of decellularized matrix for future tissue engineering applications, as well as developing a practical strategy for functional tendon

  8. Fibrocartilage associated with human tendons and their pulleys.

    Science.gov (United States)

    Benjamin, M; Qin, S; Ralphs, J R

    1995-12-01

    The presence of fibrocartilage in tendons that wrap around bony or fibrous pulleys is well known. It is an adaptation to resisting compression or shear, but the extent to which the structure of most human tendons is modified where they contact pulleys is less clear, for there has been no single comprehensive survey of a large number of sites. Less is known of the structure of the corresponding pulleys. In the present study, 38 regions of tendons that wrap around bony pulleys or pass beneath fibrous retinacula have been studied in routine histology sections taken from each of 2 or 3 elderly dissecting room cadavers. Most of the corresponding pulleys have also been examined. Fibrocartilage was present in 22 of the 38 tendon sites and it was most conspicuous where the tendons pressed predominantly against bone rather than retinacula and where they showed a large change in direction. Fibrocartilage was more characteristic of tendons at the ankle than the wrist, probably because the long axis of the foot is at right angles to that of the leg. There was considerable variation in the structure of tendon fibrocartilage. The most fibrocartilaginous tendons had oval or round cells embedded in a highly metachromatic matrix with interwoven or spiralling collagen fibres. At other sites, fibrocartilage cells were arranged in rows between parallel collagen fibres. The differences probably relate to differences in development. A single tendon could be modified at successive points along its length and fibrocartilage could be present in the endotenon and epitenon as well as in the tendon itself. Pathological changes seen in 'wrap around' tendons were fragmentation and partial delamination of the compressed surface, chondrocyte clustering, fatty infiltration and bone formation. Three types of pulleys were described for tendons--bony prominences and grooves, fibrous retinacula and synovial joints. The extent of cartilaginous differentiation on the periosteum of bony pulleys

  9. The Achilles tendon: fundamental properties and mechanisms governing healing

    Science.gov (United States)

    Freedman, Benjamin R.; Gordon, Joshua A.; Soslowsky, Louis J.

    2014-01-01

    Summary This review highlights recent research on Achilles tendon healing, and comments on the current clinical controversy surrounding the diagnosis and treatment of injury. The processes of Achilles tendon healing, as demonstrated through changes in its structure, composition, and biomechanics, are reviewed. Finally, a review of tendon developmental biology and mechano transductive pathways is completed to recognize recent efforts to augment injured Achilles tendons, and to suggest potential future strategies for therapeutic intervention and functional tissue engineering. Despite an abundance of clinical evidence suggesting that current treatments and rehabilitation strategies for Achilles tendon ruptures are equivocal, significant questions remain to fully elucidate the basic science mechanisms governing Achilles tendon injury, healing, treatment, and rehabilitation. PMID:25332943

  10. Tendon Gradient Mineralization for Tendon to Bone Interface Integration

    Science.gov (United States)

    Qu, Jin; Thoreson, Andrew R.; Chen, Qingshan; An, Kai-Nan; Amadio, Peter C.; Zhao, Chunfeng

    2014-01-01

    Tendon-to-bone integration is a great challenge for tendon or ligament reconstruction regardless of use of autograft or allograft tendons. We mineralized the tendon, thus transforming the tendon-to-bone into a “bone-to-bone” interface for healing. Sixty dog flexor digitorum profundus (FDP) tendons were divided randomly into 5 groups: 1) normal FDP tendon, 2) CaP (Non-extraction and mineralization without fetuin), 3) CaPEXT (Extraction by Na2HPO4 and mineralization without fetuin), 4) CaPFetuin (Non-extraction and mineralization with fetuin), and 5) CaPEXTFetuin (Extraction and mineralization with fetuin). The calcium and phosphate content significantly increased in tendons treated with combination of extraction and fetuin compared to the other treatments. Histology also revealed a dense mineral deposition throughout the tendon outer layers and penetrated into the tendon to a depth of 200 μm in a graded manner. Compressive moduli were significantly lower in the four mineralized groups compared with normal control group. No significant differences in maximum failure strength or stiffness were found in the suture pull-out test among all groups. Mineralization of tendon alters the interface from tendon to bone into mineralized tendon to bone, which may facilitate tendon-to-bone junction healing following tendon or ligament reconstruction. PMID:23939935

  11. Peroneal tendon disorders.

    Science.gov (United States)

    Davda, Kinner; Malhotra, Karan; O'Donnell, Paul; Singh, Dishan; Cullen, Nicholas

    2017-06-01

    Pathological abnormality of the peroneal tendons is an under-appreciated source of lateral hindfoot pain and dysfunction that can be difficult to distinguish from lateral ankle ligament injuries.Enclosed within the lateral compartment of the leg, the peroneal tendons are the primary evertors of the foot and function as lateral ankle stabilisers.Pathology of the tendons falls into three broad categories: tendinitis and tenosynovitis, tendon subluxation and dislocation, and tendon splits and tears. These can be associated with ankle instability, hindfoot deformity and anomalous anatomy such as a low lying peroneus brevis or peroneus quartus.A thorough clinical examination should include an assessment of foot type (cavus or planovalgus), palpation of the peronei in the retromalleolar groove on resisted ankle dorsiflexion and eversion as well as testing of lateral ankle ligaments.Imaging including radiographs, ultrasound and MRI will help determine the diagnosis. Treatment recommendations for these disorders are primarily based on case series and expert opinion.The aim of this review is to summarise the current understanding of the anatomy and diagnostic evaluation of the peroneal tendons, and to present both conservative and operative management options of peroneal tendon lesions. Cite this article: EFORT Open Rev 2017;2:281-292. DOI: 10.1302/2058-5241.2.160047.

  12. Tendon neuroplastic training: changing the way we think about tendon rehabilitation: a narrative review

    Science.gov (United States)

    Rio, Ebonie; Kidgell, Dawson; Moseley, G Lorimer; Docking, Sean; Purdam, Craig; Cook, Jill

    2016-01-01

    Tendinopathy can be resistant to treatment and often recurs, implying that current treatment approaches are suboptimal. Rehabilitation programmes that have been successful in terms of pain reduction and return to sport outcomes usually include strength training. Muscle activation can induce analgesia, improving self-efficacy associated with reducing one's own pain. Furthermore, strength training is beneficial for tendon matrix structure, muscle properties and limb biomechanics. However, current tendon rehabilitation may not adequately address the corticospinal control of the muscle, which may result in altered control of muscle recruitment and the consequent tendon load, and this may contribute to recalcitrance or symptom recurrence. Outcomes of interest include the effect of strength training on tendon pain, corticospinal excitability and short interval cortical inhibition. The aims of this concept paper are to: (1) review what is known about changes to the primary motor cortex and motor control in tendinopathy, (2) identify the parameters shown to induce neuroplasticity in strength training and (3) align these principles with tendon rehabilitation loading protocols to introduce a combination approach termed as tendon neuroplastic training. Strength training is a powerful modulator of the central nervous system. In particular, corticospinal inputs are essential for motor unit recruitment and activation; however, specific strength training parameters are important for neuroplasticity. Strength training that is externally paced and akin to a skilled movement task has been shown to not only reduce tendon pain, but modulate excitatory and inhibitory control of the muscle and therefore, potentially tendon load. An improved understanding of the methods that maximise the opportunity for neuroplasticity may be an important progression in how we prescribe exercise-based rehabilitation in tendinopathy for pain modulation and potentially restoration of the corticospinal

  13. Adequacy of palmaris longus and plantaris tendons for tendon grafting.

    Science.gov (United States)

    Jakubietz, Michael G; Jakubietz, Danni F; Gruenert, Joerg G; Zahn, Robert; Meffert, Rainer H; Jakubietz, Rafael G

    2011-04-01

    The reconstruction of tendon defects is challenging. The palmaris longus and plantaris tendon are generally considered best for tendon grafting. Only a few studies have examined whether these tendons, when present, meet criteria for successful grafting. The purpose of this study was to evaluate these tendons in regard to adequacy as tendon grafts. To evaluate adequacy for grafting, the palmaris longus and plantaris tendons were harvested from 92 arms and legs of 46 cadavers. Macroscopic evaluation and measurements concerning presence, length, and diameter of the tendons were obtained. Criteria for adequacy were a minimum length of 15 cm with diameter of 3 mm or, alternatively, 30 cm with a diameter of 1.5 mm. The palmaris longus tendon was present bilaterally in 36 cases and was absent bilaterally in 4 cases. The plantaris tendon was present bilaterally in 38 cases and absent bilaterally in 4 cases. In 29 cadavers, the palmaris longus tendon did not meet the criteria to be used as a tendon graft. Only in 8 cases were the tendons satisfactory for grafting bilaterally. The plantaris tendon met criteria for grafting in 20 cases bilaterally. In 17 cases, the tendons were considered inadequate bilaterally. Despite their presence, the palmaris longus and plantaris tendons are adequate for grafting less often than previously thought. In less than 50%, the tendons, although present, would serve as useful grafts. Our findings underscore the importance of choosing a second donor site before surgery in case the primarily selected tendon is not found to be suitable. Copyright © 2011 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  14. Longitudinal Long-term Magnetic Resonance Imaging and Clinical Follow-up After Single-Row Arthroscopic Rotator Cuff Repair: Clinical Superiority of Structural Tendon Integrity.

    Science.gov (United States)

    Heuberer, Philipp R; Smolen, Daniel; Pauzenberger, Leo; Plachel, Fabian; Salem, Sylvia; Laky, Brenda; Kriegleder, Bernhard; Anderl, Werner

    2017-05-01

    The number of arthroscopic rotator cuff surgeries is consistently increasing. Although generally considered successful, the reported number of retears after rotator cuff repair is substantial. Short-term clinical outcomes are reported to be rarely impaired by tendon retears, whereas to our knowledge, there is no study documenting long-term clinical outcomes and tendon integrity after arthroscopic rotator cuff repair. To investigate longitudinal long-term repair integrity and clinical outcomes after arthroscopic rotator cuff reconstruction. Case series; Level of evidence, 4. Thirty patients who underwent arthroscopic rotator cuff repair with suture anchors for a full-tendon full-thickness tear of the supraspinatus or a partial-tendon full-thickness tear of the infraspinatus were included. Two and 10 years after initial arthroscopic surgery, tendon integrity was analyzed using magnetic resonance imaging (MRI). The University of California, Los Angeles (UCLA) score and Constant score as well as subjective questions regarding satisfaction with the procedure and return to normal activity were used to evaluate short- and long-term outcomes. At the early MRI follow-up, 42% of patients showed a full-thickness rerupture, while 25% had a partial rerupture, and 33% of tendons remained intact. The 10-year MRI follow-up (129 ± 11 months) showed 50% with a total rerupture, while the other half of the tendons were partially reruptured (25%) or intact (25%). The UCLA and Constant scores significantly improved from preoperatively (UCLA total: 50.6% ± 20.2%; Constant total: 44.7 ± 10.5 points) to 2 years (UCLA total: 91.4% ± 16.0% [ P Arthroscopic rotator cuff repair showed good clinical long-term results despite a high rate of retears. Nonetheless, intact tendons provided significantly superior clinical long-term outcomes, making the improvement of tendon healing and repair integrity important goals of future research efforts.

  15. Tendon Transfers for Tetraplegia.

    Science.gov (United States)

    Bednar, Michael S

    2016-08-01

    It is estimated that 65% to 75% of patients with cervical spinal cord injuries could benefit from upper extremity tendon transfer surgery. The goals of surgery are to restore elbow extension, as well as hand pinch, grasp, and release. Patients who have defined goals, actively participate in therapy, and understand expected outcomes, appear to have the highest satisfaction following tendon transfer procedures. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Specialisation of extracellular matrix for function in tendons and ligaments

    Science.gov (United States)

    Birch, Helen L.; Thorpe, Chavaunne T.; Rumian, Adam P.

    2013-01-01

    Summary Tendons and ligaments are similar structures in terms of their composition, organisation and mechanical properties. The distinction between them stems from their anatomical location; tendons form a link between muscle and bone while ligaments link bones to bones. A range of overlapping functions can be assigned to tendon and ligaments and each structure has specific mechanical properties which appear to be suited for particular in vivo function. The extracellular matrix in tendon and ligament varies in accordance with function, providing appropriate mechanical properties. The most useful framework in which to consider extracellular matrix differences therefore is that of function rather than anatomical location. In this review we discuss what is known about the relationship between functional requirements, structural properties from molecular to gross level, cellular gene expression and matrix turnover. The relevance of this information is considered by reviewing clinical aspects of tendon and ligament repair and reconstructive procedures. PMID:23885341

  17. The tendon-to-bone attachment: Unification through disarray

    Science.gov (United States)

    Genin, Guy M.; Thomopoulos, Stavros

    2017-06-01

    High-resolution imaging, composition analysis and mechanical testing reveal a disordered transitional material within the Achilles tendon-to-bone attachment, structured as a fibrous network to enable force transfer and maximize structural integrity.

  18. History of flexor tendon repair.

    Science.gov (United States)

    Manske, Paul R

    2005-05-01

    The first issue of Hand Clinics published 20 years ago was devoted to flexor tendon injuries. This was most appropriate, because no subject in hand surgery has sparked more interest or discussion. That inaugural issue included excellent presentations on the basic science of tendon injuries (anatomy, biomechanics, nutrition, healing, adhesions) and the clinical practice of tendon repair. Of interest, there was no presentation on the fascinating history of flexor tendon surgery. It is most appropriate, therefore, that this current update of the flexor tendon begins with a historical review of the evolution of flexor tendon repair.

  19. Postinjury biomechanics of Achilles tendon vary by sex and hormone status

    Science.gov (United States)

    Fryhofer, George W.; Freedman, Benjamin R.; Hillin, Cody D.; Salka, Nabeel S.; Pardes, Adam M.; Weiss, Stephanie N.; Farber, Daniel C.

    2016-01-01

    Achilles tendon ruptures are common injuries. Sex differences are present in mechanical properties of uninjured Achilles tendon, but it remains unknown if these differences extend to tendon healing. We hypothesized that ovariectomized females (OVX) and males would exhibit inferior postinjury tendon properties compared with females. Male, female, and OVX Sprague-Dawley rats (n = 32/group) underwent acclimation and treadmill training before blunt transection of the Achilles tendon midsubstance. Injured hindlimbs were immobilized for 1 wk, followed by gradual return to activity and assessment of active and passive hindlimb function. Animals were euthanized at 3 or 6 wk postinjury to assess tendon structure, mechanics, and composition. Passive ankle stiffness and range of motion were superior in females at 3 wk; however, by 6 wk, passive and active function were similar in males and females but remained inferior in OVX. At 6 wk, female tendons had greater normalized secant modulus, viscoelastic behavior, and laxity compared with males. Normalized secant modulus, cross-sectional area and tendon glycosaminoglycan composition were inferior in OVX compared with females at 6 wk. Total fatigue cycles until tendon failure were similar among groups. Postinjury muscle fiber size was better preserved in females compared with males, and females had greater collagen III at the tendon injury site compared with males at 6 wk. Despite male and female Achilles tendons withstanding similar durations of fatigue loading, early passive hindlimb function and tendon mechanical properties, including secant modulus, suggest superior healing in females. Ovarian hormone loss was associated with inferior Achilles tendon healing. PMID:27633741

  20. Tendon transfer or tendon graft for ruptured finger extensor tendons in rheumatoid hands.

    Science.gov (United States)

    Chung, U S; Kim, J H; Seo, W S; Lee, K H

    2010-05-01

    We evaluated the clinical outcome of tendon reconstruction using tendon graft or tendon transfer and the parameters related to clinical outcome in 51 wrists of 46 patients with rheumatoid arthritis with finger extensor tendon ruptures. At a mean follow-up of 5.6 years, the mean metacarpophalangeal (MP) joint extension lag was 8 degrees (range, 0-45) and the mean visual analogue satisfaction scale was 74 (range, 10-100). Clinical outcome did not differ significantly between tendon grafting and tendon transfer. The MP joint extension lag correlated with the patient's satisfaction score, but the pulp-to-palm distance did not correlate with patient satisfaction. We conclude that both tendon grafting and tendon transfer are reliable reconstruction methods for ruptured finger extensor tendons in rheumatoid hands.

  1. MR imaging in chronic Achilles tendon disorder

    Energy Technology Data Exchange (ETDEWEB)

    Movin, T.; Rolf, C. [Section for Sports Medicine, Dept. of Orthopedic Surgery, Huddinge Univ. Hospital (Sweden); Kristoffersen-Wiberg, M.; Aspelin, P. [Dept. of Diagnostic Radiology, Karolinska Inst., Huddinge Univ. Hospital (Sweden)

    1998-03-01

    Objectives: The primary objective was to compare 4 imaging sequences (T1-weighted, T2-weighted, proton density, and T1-weighted with gadolinium contrast agent enhancement) with regard to intratendinous signal abnormality in patients with achillodynia. The secondary objective was to relate the images to the clinical symptoms and histopathological findings. Material and Methods: Twenty patients (16 men, 4 women, median age 40 years) with chronic achillodynia participated in the study. The symptoms prohibited activity and clinical examination revealed swelling and tenderness 1.5-6 cm proximal to the Achilles tendon insertion. Of the 20 patients: 5 had bilateral achillodynia, 4 had had previous contralateral Achilles tendon disorder, and 11 had never had symptoms in the contralateral tendon region. These 11 tendons served as controls for comparison. MR imaging was performed on a superconductive 1.5 T unit. Both Achilles tendons were examined (n=40) at the same time, and multiple sagittal and transversal images were obtained. The corresponding sections on these images were visually graded according to both extension and level of MR signal intensity. Tissue was obtained for microscopic examination from the most symptomatic side in all patients (n=20). Results: T1-weighted images following gadolinium contrast medium enhancement proved to be the best method by which to visualize intratendinous signal abnormality. This sequence revealed signal abnormality in 24/25 symptomatic tendons and in 1/11 control tendons. Histopathological examination showed an increased noncollagenous extracellular matrix and altered fiber structure in the lesions corresponding to the contrast-enhanced areas. (orig./MG).

  2. [Achilles tendon rupture].

    Science.gov (United States)

    Thermann, H; Hüfner, T; Tscherne, H

    2000-03-01

    The treatment of acute of Achilles tendon rupture experienced a dynamic development in the last ten years. Decisive for this development was the application of MRI and above all the ultrasonography in the diagnostics of the pathological changes and injuries of tendons. The question of rupture morphology as well as different courses of healing could be now evaluated objectively. These advances led consequently to new modalities in treatment concepts and rehabilitation protocols. The decisive input for improvements of the outcome results and particularly the shortening of the rehabilitation period came with introduction of the early functional treatment in contrast to immobilizing plaster treatment. In a prospective randomized study (1987-1989) at the Trauma Dept. of the Hannover Medical School could show no statistical differences comparing functional non-operative with functional operative therapy with a special therapy boot (Variostabil/Adidas). The crucial criteria for therapy selection results from the sonographically measured position of the tendon stumps in plantar flexion (20 degrees). With complete adaptation of the tendons' ends surgical treatment does not achieve better results than non-operative functional treatment in term of tendon healing and functional outcome. Regarding the current therapeutic standards each method has is advantages and disadvantages. Both, the operative and non-operative functional treatment enable a stable tendon healing with a low risk of re-rupture (1-2%). Meanwhile there is consensus for early functional after-treatment of the operated Achilles' tendons. There seems to be a trend towards non-operative functional treatment in cases of adequate sonographical findings, or to minimal invasive surgical techniques.

  3. Mesenchymal stem cells and insulin-like growth factor-I gene-enhanced mesenchymal stem cells improve structural aspects of healing in equine flexor digitorum superficialis tendons.

    Science.gov (United States)

    Schnabel, Lauren V; Lynch, Maureen E; van der Meulen, Marjolein C H; Yeager, Amy E; Kornatowski, Matthew A; Nixon, Alan J

    2009-10-01

    Tendinitis remains a catastrophic injury among athletes. Mesenchymal stem cells (MSCs) have recently been investigated for use in the treatment of tendinitis. Previous work has demonstrated the value of insulin-like growth factor-I (IGF-I) to stimulate cellular proliferation and tendon fiber deposition in the core lesion of tendinitis. This study examined the effects of MSCs, as well as IGF-I gene-enhanced MSCs (AdIGF-MSCs) on tendon healing in vivo. Collagenase-induced bilateral tendinitis lesions were created in equine flexor digitorum superficialis tendons (SDFT). Tendons were treated with 10 x 10(6) MSCs or 10 x 10(6) AdIGF-MSCs. Control limbs were injected with 1 mL of phosphate-buffered saline (PBS). Ultrasound examinations were performed at t = 0, 2, 4, 6, and 8 weeks. Horses were euthanized at 8 weeks and SDFTs were mechanically tested to failure and evaluated for biochemical composition and histologic characteristics. Expression of collagen types I and III, IGF-I, cartilage oligomeric matrix protein (COMP), matrix metalloproteinase-3 (MMP-3), matrix metalloproteinase-13 (MMP-13), and aggrecanase-1 (ADAMTS-4) were similar in MSC and control tendons. Both MSC and AdIGF-MSC injection resulted in significantly improved tendon histological scores. These findings indicate a benefit to the use of MSCs and AdIGF-MSCs for the treatment of tendinitis. (c) 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  4. Steroid injections - tendon, bursa, joint

    Science.gov (United States)

    ... gov/ency/article/007678.htm Steroid injections - tendon, bursa, joint To use the sharing features on this ... can be injected into a joint, tendon, or bursa. Description Your health care provider inserts a small ...

  5. Tendon Driven Finger Actuation System

    Science.gov (United States)

    Ihrke, Chris A. (Inventor); Reich, David M. (Inventor); Bridgwater, Lyndon (Inventor); Linn, Douglas Martin (Inventor); Askew, Scott R. (Inventor); Diftler, Myron A. (Inventor); Platt, Robert (Inventor); Hargrave, Brian (Inventor); Valvo, Michael C. (Inventor); Abdallah, Muhammad E. (Inventor); hide

    2013-01-01

    A humanoid robot includes a robotic hand having at least one finger. An actuation system for the robotic finger includes an actuator assembly which is supported by the robot and is spaced apart from the finger. A tendon extends from the actuator assembly to the at least one finger and ends in a tendon terminator. The actuator assembly is operable to actuate the tendon to move the tendon terminator and, thus, the finger.

  6. Clinical aspects of tendon healing

    NARCIS (Netherlands)

    J.C.H.M. van der Meulen (Jacques)

    1974-01-01

    textabstractWe know that healing of a tendon wound takes place by an invasion of fibreblasts from the surrounding tissues; the tendon itself has no intrinsic healing capacity. lt was Potenza (1962) who proved that a traumatic suture of the tendons within their sheath is followed by disintegration of

  7. Sex Hormones and Tendon

    DEFF Research Database (Denmark)

    Hansen, Mette; Kjaer, Michael

    2016-01-01

    The risk of overuse and traumatic tendon and ligament injuries differ between women and men. Part of this gender difference in injury risk is probably explained by sex hormonal differences which are specifically distinct during the sexual maturation in the teenage years and during young adulthood....... The effects of the separate sex hormones are not fully elucidated. However, in women, the presence of estrogen in contrast to very low estrogen levels may be beneficial during regular loading of the tissue or during recovering after an injury, as estrogen can enhance tendon collagen synthesis rate. Yet...

  8. Open Achilles tendon lacerations.

    Science.gov (United States)

    Said, M Nader; Al Ateeq Al Dosari, Mohamed; Al Subaii, Nasser; Kawas, Alaa; Al Mas, Ali; Al Ser, Yaser; Abuodeh, Yousef; Shakil, Malik; Habash, Ali; Mukhter, Khalid

    2015-04-01

    In contrast to closed Achilles tendon ruptures, open injuries are rarely reported in the literature. This paper provides information about open Achilles tendon wounds that are eventually seen in the Middle East. The reporting unit, Hamad Medical Corporation, is one of the biggest trauma centers in the Gulf area and the major health provider in Qatar. This is a retrospective study including patients admitted and operated for open Achilles tendon injuries between January 2011 and December 2013. Two hundred and five cases of open Achilles tendon lacerations were operated in Hamad General Hospital in this period. Forty-eight cases showed partial injuries, and the remaining are complete tendons cut. In the same period, fifty-one closed ruptured Achilles tendons were operated in the same trauma unit. In the majority of cases, the open injury resulted from a slip in the floor-leveled traditional toilette seats. Local damage to the toilette seats resulted in sharp edges causing the laceration of the heel if the patient was slipping over the wet floor. This occurrence is the cause in the vast majority of the cases. Wounds were located 1-5 cm proximal to tendon insertion. Standard treatment principles were applied. This included thorough irrigation in the emergency room, intravenous antibiotics, surgical debridement and primary repair within 24 h. Patients were kept in the hospital 1-7 days for intravenous antibiotics and possible dressing changes. Postoperatively below knee slabs were applied in the majority of patients and were kept for about 4 weeks followed by gradual weight bearing and range of motion exercises. Outpatients follow up in 1-2 weeks. Further follow-up visits at around 2-, 4-, 8- and 12-week intervals until complete wound healing and satisfactory rehabilitation outcome. Sixteen cases needed a second procedure. A high incidence of Achilles tendon open injuries is reported. This seems to be related to partially damaged floor-level toilettes in the

  9. A fibre-reinforced poroviscoelastic model accurately describes the biomechanical behaviour of the rat Achilles tendon.

    Directory of Open Access Journals (Sweden)

    Hanifeh Khayyeri

    Full Text Available Computational models of Achilles tendons can help understanding how healthy tendons are affected by repetitive loading and how the different tissue constituents contribute to the tendon's biomechanical response. However, available models of Achilles tendon are limited in their description of the hierarchical multi-structural composition of the tissue. This study hypothesised that a poroviscoelastic fibre-reinforced model, previously successful in capturing cartilage biomechanical behaviour, can depict the biomechanical behaviour of the rat Achilles tendon found experimentally.We developed a new material model of the Achilles tendon, which considers the tendon's main constituents namely: water, proteoglycan matrix and collagen fibres. A hyperelastic formulation of the proteoglycan matrix enabled computations of large deformations of the tendon, and collagen fibres were modelled as viscoelastic. Specimen-specific finite element models were created of 9 rat Achilles tendons from an animal experiment and simulations were carried out following a repetitive tensile loading protocol. The material model parameters were calibrated against data from the rats by minimising the root mean squared error (RMS between experimental force data and model output.All specimen models were successfully fitted to experimental data with high accuracy (RMS 0.42-1.02. Additional simulations predicted more compliant and soft tendon behaviour at reduced strain-rates compared to higher strain-rates that produce a stiff and brittle tendon response. Stress-relaxation simulations exhibited strain-dependent stress-relaxation behaviour where larger strains produced slower relaxation rates compared to smaller strain levels. Our simulations showed that the collagen fibres in the Achilles tendon are the main load-bearing component during tensile loading, where the orientation of the collagen fibres plays an important role for the tendon's viscoelastic response. In conclusion, this

  10. A fibre-reinforced poroviscoelastic model accurately describes the biomechanical behaviour of the rat Achilles tendon.

    Science.gov (United States)

    Khayyeri, Hanifeh; Gustafsson, Anna; Heuijerjans, Ashley; Matikainen, Marko K; Julkunen, Petro; Eliasson, Pernilla; Aspenberg, Per; Isaksson, Hanna

    2015-01-01

    Computational models of Achilles tendons can help understanding how healthy tendons are affected by repetitive loading and how the different tissue constituents contribute to the tendon's biomechanical response. However, available models of Achilles tendon are limited in their description of the hierarchical multi-structural composition of the tissue. This study hypothesised that a poroviscoelastic fibre-reinforced model, previously successful in capturing cartilage biomechanical behaviour, can depict the biomechanical behaviour of the rat Achilles tendon found experimentally. We developed a new material model of the Achilles tendon, which considers the tendon's main constituents namely: water, proteoglycan matrix and collagen fibres. A hyperelastic formulation of the proteoglycan matrix enabled computations of large deformations of the tendon, and collagen fibres were modelled as viscoelastic. Specimen-specific finite element models were created of 9 rat Achilles tendons from an animal experiment and simulations were carried out following a repetitive tensile loading protocol. The material model parameters were calibrated against data from the rats by minimising the root mean squared error (RMS) between experimental force data and model output. All specimen models were successfully fitted to experimental data with high accuracy (RMS 0.42-1.02). Additional simulations predicted more compliant and soft tendon behaviour at reduced strain-rates compared to higher strain-rates that produce a stiff and brittle tendon response. Stress-relaxation simulations exhibited strain-dependent stress-relaxation behaviour where larger strains produced slower relaxation rates compared to smaller strain levels. Our simulations showed that the collagen fibres in the Achilles tendon are the main load-bearing component during tensile loading, where the orientation of the collagen fibres plays an important role for the tendon's viscoelastic response. In conclusion, this model can capture

  11. Striated muscle fiber apoptosis after experimental tendon lesion in a rat model.

    Science.gov (United States)

    Palumbo, Carla; Rovesta, Claudio; Ferretti, Marzia

    2012-10-01

    Tendon lesions induce muscular atrophy, the nature of which has not yet been clearly related to lesion etiology and entity. In the present study, tendon and muscle alterations were assessed after experimental tendon lesion of the Infraspinatus muscle in young rats. The consequences of lesions differed on the basis of both extension and injured tissue vascularization, that is apoptosis and/or degeneration, differing mainly by energy demands: apoptosis requires high energy levels (proportional to vascular supply), but degeneration does not. It is well known that tendons are poorly supplied with blood compared with muscular masses, which are abundantly vascularized. Five weeks after tendon surgical section, tendon/muscle samples were taken for TUNEL and transmission electron microscopy. The structural results reported here identified different tendon/muscle alterations: degeneration of tendon without signs of apoptosis, and atrophy of muscle fibers due only to apoptosis. This led to the formulation of the following hypothetical sequence of events: a tendon lesion, not recovering quickly due to the poor tendon blood supply, results in degeneration of the injured tendon, which, in turn, induces a partial disuse of the muscle mass, which consequently atrophies (proportionally to the severity of tendon lesion) by striated muscular fiber apoptosis. The authors suggest that the different behavior of the two tissues depends on the marked difference in their vascularization. © 2012 The Authors Journal of Anatomy © 2012 Anatomical Society.

  12. Fibrocartilage associated with human tendons and their pulleys.

    OpenAIRE

    Benjamin, M; Qin, S; Ralphs, J R

    1995-01-01

    The presence of fibrocartilage in tendons that wrap around bony or fibrous pulleys is well known. It is an adaptation to resisting compression or shear, but the extent to which the structure of most human tendons is modified where they contact pulleys is less clear, for there has been no single comprehensive survey of a large number of sites. Less is known of the structure of the corresponding pulleys. In the present study, 38 regions of tendons that wrap around bony pulleys or pass beneath f...

  13. Insulin-like growth factor I enhances collagen synthesis in engineered human tendon tissue

    DEFF Research Database (Denmark)

    Herchenhan, Andreas; Bayer, Monika L.; Eliasson, Pernilla

    2015-01-01

    investigated the influence of insulin-like growth factor I (IGF-I) on tendon construct formation in 3D cell culture. DESIGN: Tendon constructs were grown in 0.5 or 10% FBS with or without IGF-I (250 mg/ml) supplementation. Collagen content (fluorometric), mRNA levels (PCR) and fibril diameter (transmission...... of fibril diameter (day 14), collagen content (at days 21 and 28) and mRNA expression for collagen, tenomodulin and scleraxis. CONCLUSION: IGF-I supplementation promotes early onset of tensile load induced collagen formation and tendon structural arrangement, whereas the FBS concentration routinely used......OBJECTIVE: Isolated human tendon cells form 3D tendon constructs that demonstrate collagen fibrillogenesis and feature structural similarities to tendon when cultured under tensile load. The exact role of circulating growth factors for collagen formation in tendon is sparsely examined. We...

  14. Experimental studies in chickens on the initial nutrition of tendon grafts.

    Science.gov (United States)

    Manske, P R; Lesker, P A; Bridwell, K

    1979-11-01

    A study of nutrition of various tendon graft preparations in adult chickens (up to 2 weeks after grafting), using tritiated proline and a trichloracetic acid extraction technique which separated the free and metabolized amino acid fractions, suggests that diffusion of nutrients is an important process in the initial nutrition of tendon grafts, that tendon grafts are metabolically active and viable structures, that adhesions which are frequently associated with tendon grafts do not appear to be essential to the nutrition of grafts, and that tendon grafts within fibrous pseudosheaths are nourished as effectively as grafts within synovial sheaths.

  15. Tendon material properties vary and are interdependent among turkey hindlimb muscles

    Science.gov (United States)

    Matson, Andrew; Konow, Nicolai; Miller, Samuel; Konow, Pernille P.; Roberts, Thomas J.

    2012-01-01

    SUMMARY The material properties of a tendon affect its ability to store and return elastic energy, resist damage, provide mechanical feedback and amplify or attenuate muscle power. While the structural properties of a tendon are known to respond to a variety of stimuli, the extent to which material properties vary among individual muscles remains unclear. We studied the tendons of six different muscles in the hindlimb of Eastern wild turkeys to determine whether there was variation in elastic modulus, ultimate tensile strength and resilience. A hydraulic testing machine was used to measure tendon force during quasi-static lengthening, and a stress–strain curve was constructed. There was substantial variation in tendon material properties among different muscles. Average elastic modulus differed significantly between some tendons, and values for the six different tendons varied nearly twofold, from 829±140 to 1479±106 MPa. Tendons were stretched to failure, and the stress at failure, or ultimate tensile stress, was taken as a lower-limit estimate of tendon strength. Breaking tests for four of the tendons revealed significant variation in ultimate tensile stress, ranging from 66.83±14.34 to 112.37±9.39 MPa. Resilience, or the fraction of energy returned in cyclic length changes was generally high, and one of the four tendons tested was significantly different in resilience from the other tendons (range: 90.65±0.83 to 94.02±0.71%). An analysis of correlation between material properties revealed a positive relationship between ultimate tensile strength and elastic modulus (r2=0.79). Specifically, stiffer tendons were stronger, and we suggest that this correlation results from a constrained value of breaking strain, which did not vary significantly among tendons. This finding suggests an interdependence of material properties that may have a structural basis and may explain some adaptive responses observed in studies of tendon plasticity. PMID:22771746

  16. Achilles tendon rupture - aftercare

    Science.gov (United States)

    ... will cover your foot and go to your knee. Your toes will be pointing downward. The cast will be changed every 2 to 3 weeks to help stretch your tendon. If you have a leg brace, splint, or boot, it will keep you from ...

  17. Different Achilles Tendon Pathologies Show Distinct Histological and Molecular Characteristics

    Directory of Open Access Journals (Sweden)

    Franka Klatte-Schulz

    2018-01-01

    Full Text Available Reasons for the development of chronic tendon pathologies are still under debate and more basic knowledge is needed about the different diseases. The aim of the present study was therefore to characterize different acute and chronic Achilles tendon disorders. Achilles tendon samples from patients with chronic tendinopathy (n = 7, chronic ruptures (n = 6, acute ruptures (n = 13, and intact tendons (n = 4 were analyzed. The histological score investigating pathological changes was significantly increased in tendinopathy and chronic ruptures compared to acute ruptures. Inflammatory infiltration was detected by immunohistochemistry in all tendon pathology groups, but was significantly lower in tendinopathy compared to chronic ruptures. Quantitative real-time PCR (qRT-PCR analysis revealed significantly altered expression of genes related to collagens and matrix modeling/remodeling (matrix metalloproteinases, tissue inhibitors of metalloproteinases in tendinopathy and chronic ruptures compared to intact tendons and/or acute ruptures. In all three tendon pathology groups markers of inflammation (interleukin (IL 1β, tumor necrosis factor α, IL6, IL10, IL33, soluble ST2, transforming growth factor β1, cyclooxygenase 2, inflammatory cells (cluster of differentaition (CD 3, CD68, CD80, CD206, fat metabolism (fatty acid binding protein 4, peroxisome proliferator-activated receptor γ, CCAAT/enhancer-binding protein α, adiponectin, and innervation (protein gene product 9.5, growth associated protein 43, macrophage migration inhibitory factor were detectable, but only in acute ruptures significantly regulated compared to intact tendons. The study gives an insight into structural and molecular changes of pathological processes in tendons and might be used to identify targets for future therapy of tendon pathologies.

  18. Finite-Element Numerical Simulation of the Bending Performance of Post-Tensioned Structural Glass Beams with Adhesively Bonded CFRP Tendons

    NARCIS (Netherlands)

    Bedon, Chiara; Louter, P.C.

    2016-01-01

    In this paper, a Finite-Element (FE) numerical investigation is carried out on laminated glass beams with Carbon Fibre Reinforced Polymer (CFRP) adhesively bonded post-tensioning tendons. Taking advantage of past four-point bending experimental test results available in literature, a refined full 3D

  19. Tendon injuries of the hand

    Science.gov (United States)

    Schöffl, Volker; Heid, Andreas; Küpper, Thomas

    2012-01-01

    Tendon injuries are the second most common injuries of the hand and therefore an important topic in trauma and orthopedic patients. Most injuries are open injuries to the flexor or extensor tendons, but less frequent injuries, e.g., damage to the functional system tendon sheath and pulley or dull avulsions, also need to be considered. After clinical examination, ultrasound and magnetic resonance imaging have proved to be important diagnostic tools. Tendon injuries mostly require surgical repair, dull avulsions of the distal phalanges extensor tendon can receive conservative therapy. Injuries of the flexor tendon sheath or single pulley injuries are treated conservatively and multiple pulley injuries receive surgical repair. In the postoperative course of flexor tendon injuries, the principle of early passive movement is important to trigger an “intrinsic” tendon healing to guarantee a good outcome. Many substances were evaluated to see if they improved tendon healing; however, little evidence was found. Nevertheless, hyaluronic acid may improve intrinsic tendon healing. PMID:22720265

  20. [Questions concerning two-stage reconstruction of injured flexor tendons. III. Ultrastructure of the tenosynovium in the pseudo-tendon sheath created by using a silicone rod].

    Science.gov (United States)

    Salamon, A; Bíró, V; Vámhidy, L; Trombitás, K; Józsa, L

    1993-01-01

    Authors have investigated the ultrastructure of the pseudo tendon sheath, formed with silicon rod and man. They have observed a superficial structure, resembling the normal tendon sheath in scanning electron microscopic examination. With transmission electron microscopy phagocyte "A" type and secretion "B" type synovial cells were found. Authors state that the newly formed tenosynovium has an important role in the nutrition of the tendon graft and the prevention of adhesions.

  1. Miscellaneous conditions of tendons, tendon sheaths, and ligaments.

    Science.gov (United States)

    Dyson, S J; Dik, K J

    1995-08-01

    The use of diagnostic ultrasonography has greatly enhances our ability to diagnose injuries of tendons and tendon sheaths that were previously either unrecognized or poorly understood. For may of these injuries, there is currently only a small amount of follow-up data. This article considers injuries of the deep digital flexor tendon and its accessory ligament, the carpal tunnel syndrome soft tissue swellings on the dorsal aspect of the carpus, intertubercular (bicipital) bursitis and bicipital tendinitis, injuries of the gastrocnemius tendon, common calcaneal tendinitis, rupture of peroneus (fibularis tertius) and ligaments injuries of the back.

  2. The initiation of embryonic-like collagen fibrillogenesis by adult human tendon fibroblasts when cultured under tension

    DEFF Research Database (Denmark)

    Bayer, Monika L; Yeung, Chin-Yan C; Kadler, Karl E

    2010-01-01

    Tendon fibroblasts synthesize collagen and form fibrils during embryonic development, but to what extent mature fibroblasts are able to recapitulate embryonic development and develop normal tendon structure is unknown. The present study examined the capability of mature human tendon fibroblasts t...

  3. Suture materials and suture techniques used in tendon repair.

    Science.gov (United States)

    Ketchum, L D

    1985-02-01

    . The less traumatic suture techniques facilitate closure of the tendon sheath, which not only acts as a mechanical barrier to the ingrowth of extrasheath adhesion, which produces fibroblasts, but also re-establishes the continuity of the synovial fluid system, which is a major source of nutrition to the tendon. The healing tendon then can be thought of as a delicate structure, one not to be overmanipulated, traumatized, strangulated, or stretched.(ABSTRACT TRUNCATED AT 400 WORDS)

  4. Palmar and digital flexor tendon pulleys.

    Science.gov (United States)

    Doyle, J R

    2001-02-01

    Retinacular structures, called pulleys, maintain the flexor tendons of the hand in constant relationship to the joint axes and promote economy and efficiency in finger flexion. This system is composed of the transverse carpal ligament, the palmar aponeurosis pulley, and the digital flexor pulley system. Of these three components, the digital pulleys are the most critical to finger flexion. In their normal state, these pulley components are ideal in all aspects including configuration and location, which accomodates a 260 degrees arc of motion without impingement and with minimum friction while at the same time using muscle tendon excursion that is well within the natural range of the muscle. An absent pulley results in an increased moment arm and requires increased tendon excursion to produce the same arc of motion. Because muscle excursion is not a limitless factor and is directly proportional to muscle fiber length, the effectiveness of tendon excursion is dependent on maintenance of the critical relationship between pulleys and the adjacent joints. Preservation and reconstruction of this system is based on knowledge of the anatomy and an understanding of the relative functional significance of each component of the system.

  5. Achilles tendon of wistar rats treated with laser therapy and eccentric exercise

    Directory of Open Access Journals (Sweden)

    Maria Verônica de Souza

    2015-10-01

    as a healthy tendon. On the other hand, it also does not influence negatively the structure and function of the Achilles tendon.

  6. Mineral distributions at the developing tendon enthesis.

    Directory of Open Access Journals (Sweden)

    Andrea G Schwartz

    Full Text Available Tendon attaches to bone across a functionally graded interface, "the enthesis". A gradient of mineral content is believed to play an important role for dissipation of stress concentrations at mature fibrocartilaginous interfaces. Surgical repair of injured tendon to bone often fails, suggesting that the enthesis does not regenerate in a healing setting. Understanding the development and the micro/nano-meter structure of this unique interface may provide novel insights for the improvement of repair strategies. This study monitored the development of transitional tissue at the murine supraspinatus tendon enthesis, which begins postnatally and is completed by postnatal day 28. The micrometer-scale distribution of mineral across the developing enthesis was studied by X-ray micro-computed tomography and Raman microprobe spectroscopy. Analyzed regions were identified and further studied by histomorphometry. The nanometer-scale distribution of mineral and collagen fibrils at the developing interface was studied using transmission electron microscopy (TEM. A zone (∼20 µm exhibiting a gradient in mineral relative to collagen was detected at the leading edge of the hard-soft tissue interface as early as postnatal day 7. Nanocharacterization by TEM suggested that this mineral gradient arose from intrinsic surface roughness on the scale of tens of nanometers at the mineralized front. Microcomputed tomography measurements indicated increases in bone mineral density with time. Raman spectroscopy measurements revealed that the mineral-to-collagen ratio on the mineralized side of the interface was constant throughout postnatal development. An increase in the carbonate concentration of the apatite mineral phase over time suggested possible matrix remodeling during postnatal development. Comparison of Raman-based observations of localized mineral content with histomorphological features indicated that development of the graded mineralized interface is linked

  7. Wide-Awake Primary Flexor Tendon Repair, Tenolysis, and Tendon Transfer

    OpenAIRE

    Tang, Jin Bo

    2015-01-01

    Tendon surgery is unique because it should ensure tendon gliding after surgery. Tendon surgery now can be performed under local anesthesia without tourniquet, by injecting epinephrine mixed with lidocaine, to achieve vasoconstriction in the area of surgery. This method allows the tendon to move actively during surgery to test tendon function intraoperatively and to ensure the tendon is properly repaired before leaving the operating table. I applied this method to primary flexor tendon repair ...

  8. Gastrocnemius tendon length and strain are different when assessed using straight or curved tendon model

    OpenAIRE

    Stosic, Jelena; Finni Juutinen, Taija

    2011-01-01

    The present study investigated the effects of tendon curvature on measurements of tendon length using 3D-kinematic analysis. Curved and straight tendon models were employed for assessing medial gastrocnemius tendon length and strain during hopping (N = 8). Tendon curvature was identified using small reflective markers placed on the skin surface along the length of the tendon and a sum of vectors between the markers from the calcaneous up to the marker at the origin of tendon was calculated. T...

  9. Ultrasound-guided tendon fenestration.

    Science.gov (United States)

    Chiavaras, Mary M; Jacobson, Jon A

    2013-02-01

    A potential treatment for chronic tendinosis or tendinopathy is percutaneous ultrasound-guided tendon fenestration, also termed dry needling or tenotomy. This procedure involves gently passing a needle through the abnormal tendon multiple times to change a chronic degenerative process into an acute condition that is more likely to heal. This article reviews the literature on tendon fenestration and describes the technical aspects of this procedure including postprocedural considerations. Although peer-reviewed literature on this topic is limited, studies to date have shown that ultrasound-guided tendon fenestration can improve patient symptoms. Several other percutaneous treatments for tendinopathy that include prolotherapy, autologous whole-blood injection, and autologous platelet-rich plasma injection are often performed in conjunction with fenestration. It is currently unknown if these other percutaneous procedures have any benefit over ultrasound-guided tendon fenestration alone. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  10. The effect of lubricin on the gliding resistance of mouse intrasynovial tendon.

    Directory of Open Access Journals (Sweden)

    Masanori Hayashi

    Full Text Available The purpose of this study was to investigate the role of lubricin on the gliding resistance of intrasynovial tendons by comparing lubricin knockout, heterozygous, and wild type mice. A total of thirty-six deep digital flexor (DDF tendons in the third digits of each hind paw from eighteen adult mice were used, including six lubricin knockout mice (Prg4 -/-, six heterozygous mice (Prg4 +/-, and six wild type mice (Prg4 +/+. The tendon gliding resistance was measured using a custom-made device. Tendon structural changes were evaluated by scanning electron and light microscopy. The gliding resistance of intrasynovial tendons from lubricin knockout mice was significantly higher than the gliding resistance of either wild type or heterozygous mice. The surface of the lubricin knockout tendons appeared to be rougher, compared to the wild type and heterozygous tendons. Synovial hyperplasia was found in the lubricin knockout mice. Cartilage-like tissue was found in the tendon and pulley of the lubricin knockout mice. Our findings confirm the importance of lubricin in intrasynovial tendon lubrication. This knockout model may be useful in determining the effect of lubricin on tendon healing and the response to injury.

  11. The effect of lubricin on the gliding resistance of mouse intrasynovial tendon.

    Science.gov (United States)

    Hayashi, Masanori; Zhao, Chunfeng; Thoreson, Andrew R; Chikenji, Takako; Jay, Gregory D; An, Kai-Nan; Amadio, Peter C

    2013-01-01

    The purpose of this study was to investigate the role of lubricin on the gliding resistance of intrasynovial tendons by comparing lubricin knockout, heterozygous, and wild type mice. A total of thirty-six deep digital flexor (DDF) tendons in the third digits of each hind paw from eighteen adult mice were used, including six lubricin knockout mice (Prg4 -/-), six heterozygous mice (Prg4 +/-), and six wild type mice (Prg4 +/+). The tendon gliding resistance was measured using a custom-made device. Tendon structural changes were evaluated by scanning electron and light microscopy. The gliding resistance of intrasynovial tendons from lubricin knockout mice was significantly higher than the gliding resistance of either wild type or heterozygous mice. The surface of the lubricin knockout tendons appeared to be rougher, compared to the wild type and heterozygous tendons. Synovial hyperplasia was found in the lubricin knockout mice. Cartilage-like tissue was found in the tendon and pulley of the lubricin knockout mice. Our findings confirm the importance of lubricin in intrasynovial tendon lubrication. This knockout model may be useful in determining the effect of lubricin on tendon healing and the response to injury.

  12. Males have Inferior Achilles Tendon Material Properties Compared to Females in a Rodent Model.

    Science.gov (United States)

    Pardes, A M; Freedman, B R; Fryhofer, G W; Salka, N S; Bhatt, P R; Soslowsky, L J

    2016-10-01

    The Achilles tendon is the most commonly ruptured tendon in the human body. Numerous studies have reported incidence of these injuries to be upwards of five times as common in men than women. Therefore, the objective of this study was to investigate the sex- and hormone-specific differences between Achilles tendon and muscle between female, ovariectomized female (ovarian hormone deficient), and male rats. Uninjured tissues were collected from all groups for mechanical, structural, and histological analysis. Our results showed that while cross-sectional area and failure load were increased in male tendons, female tendons exhibited superior tendon material properties and decreased muscle fiber size. Specifically, linear and dynamic moduli were increased while viscoelastic properties (e.g., hysteresis, percent relaxation) were decreased in female tendons, suggesting greater resistance to deformation under load and more efficient energy transfer, respectively. No differences were identified in tendon organization, cell shape, cellularity, or proteoglycan content. Additionally, no differences in muscle fiber type distribution were observed between groups. In conclusion, inferior tendon mechanical properties and increased muscle fiber size may explain the increased susceptibility for Achilles tendon injury observed clinically in men compared to women.

  13. Non-linear finite element model to assess the effect of tendon forces on the foot-ankle complex.

    Science.gov (United States)

    Morales-Orcajo, Enrique; Souza, Thales R; Bayod, Javier; Barbosa de Las Casas, Estevam

    2017-11-01

    A three-dimensional foot finite element model with actual geometry and non-linear behavior of tendons is presented. The model is intended for analysis of the lower limb tendon forces effect in the inner foot structure. The geometry of the model was obtained from computational tomographies and magnetic resonance images. Tendon tissue was characterized with the first order Ogden material model based on experimental data from human foot tendons. Kinetic data was employed to set the load conditions. After model validation, a force sensitivity study of the five major foot extrinsic tendons was conducted to evaluate the function of each tendon. A synergic work of the inversion-eversion tendons was predicted. Pulling from a peroneus or tibialis tendon stressed the antagonist tendons while reducing the stress in the agonist. Similar paired action was predicted for the Achilles tendon with the tibialis anterior. This behavior explains the complex control motion performed by the foot. Furthermore, the stress state at the plantar fascia, the talocrural joint cartilage, the plantar soft tissue and the tendons were estimated in the early and late midstance phase of walking. These estimations will help in the understanding of the functional role of the extrinsic muscle-tendon-units in foot pronation-supination. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

  14. Rectus Femoris Tendon Calcification

    Science.gov (United States)

    Zini, Raul; Panascì, Manlio; Papalia, Rocco; Franceschi, Francesco; Vasta, Sebastiano; Denaro, Vincenzo

    2014-01-01

    Background: Since it was developed, hip arthroscopy has become the favored treatment for femoroacetabular impingement. Due to recent considerable improvements, the indications for this technique have been widely extended. Injuries of the rectus femoris tendon origin, after an acute phase, could result in a chronic tendinopathy with calcium hydroxyapatite crystal deposition, leading to pain and loss of function. Traditionally, this condition is addressed by local injection of anesthetic and corticosteroids or, when conservative measures fail, by open excision of the calcific lesion by an anterior approach. Purpose: To assess whether arthroscopic excision of calcification of the proximal rectus is a safe and effective treatment. Study Design: Case series; Level of evidence, 4. Methods: Outcomes were studied from 6 top amateur athletes (age range, 30-43 years; mean, 32.6 years) affected by calcification of the proximal rectus who underwent arthroscopic excision of the calcification. Patients were preoperatively assessed radiographically, and diagnosis was confirmed by a 3-dimensional computed tomography scan. To evaluate the outcome, standardized hip rating scores were used pre- and postoperatively (at 6 and 12 months): the Hip disability and Osteoarthritis Outcome Score, Oxford Hip Score, and Modified Harris Hip Score. Moreover, visual analog scales (VAS) for pain, sport activity level (SAL), and activities of daily living (ADL) were also used. Results: One year after surgery, all patients reported satisfactory outcomes, with 3 of 6 rating their return-to-sport level as high as preinjury level, and the remaining 3 with a percentage higher than 80%. Five patients ranked their ability to carry on daily activities at 100%. Statistical analysis showed significant improvement of the Oxford Hip Score, the Modified Harris Hip Score, and all 3 VAS subscales (pain, SAL, and ADL) from pre- to latest postoperative assessment (P < .05). Conclusion: Arthroscopic excision of

  15. Biceps Tendon Rupture

    Directory of Open Access Journals (Sweden)

    Daniel M Polvino

    2018-01-01

    Full Text Available History of present illness: A 55-year-old male presented to the emergency department with a chief complaint of right arm pain. Five days prior to arrival, he attempted to lift himself up on his van and experienced what he described as a “rubber band snapping” in his right arm. He reported severe pain at the time that persisted but lessened in severity. Additionally, he reported increasing bruising over the proximal right arm. He had no history of prior right arm or shoulder injury. Significant findings: Physical exam was significant for ecchymosis and mild swelling of the right bicep. When the right arm was flexed at the elbow, a prominent mass was visible and palpable over the right bicep. Right upper extremity strength was 4/5 with flexion at the elbow. Discussion: The biceps brachii muscle is comprised of a long and short head, which share a common attachment at the bicipital tuberosity on the radius. The short head originates from the coracoid process of the scapula and the long head originates from the supraglenoid tubercle.1 Biceps tendon rupture has been found to occur at a rate of 0.53/100,000 over five years, and is three times more likely to occur in men than women.2 Risk factors for biceps tendon rupture include male sex, old age, increased body mass index, smoking, and pre-existing shoulder pathology.3,4 Diagnosis of biceps tendon rupture is typically a clinical diagnosis utilizing inspection and palpation as well as special testing such as the Speed’s and/or Yergason’s tests. Ultrasound may be used to aid in diagnosis; in full-thickness tears, ultrasound was found to have a sensitivity of 88% and a specificity of 98%. However, in partial thickness tears ultrasound has a sensitivity of 27% and a specificity of 100%.5 Often considered the gold standard in diagnosis, MRI has been found to have a sensitivity of only 67% and specificity of 98% in detecting complete tears6. Treatment initially consists of rest, ice, compression

  16. [Pathophysiology of overuse tendon injury].

    Science.gov (United States)

    Kannus, P; Paavola, M; Paakkala, T; Parkkari, J; Järvinen, T; Järvinen, M

    2002-10-01

    Overuse tendon injury is one of the most common injuries in sports. The etiology as well as the pathophysiological mechanisms leading to tendinopathy are of crucial medical importance. At the moment intrinsic and extrinsic factors are assumed as mechanisms of overuse tendon injury. Except for the acute, extrinsic trauma, the chronic overuse tendon injury is a multifactorial process. There are many other factors, such as local hypoxia, less of nutrition, impaired metabolism and local inflammatory that may also contribute to the development of tissue damage. The exact interaction of these factors cannot be explained entirely at the moment. Further studies will be necessary in order to get more information.

  17. Study of optical properties and proteoglycan content of tendons by polarization sensitive optical coherence tomography

    Science.gov (United States)

    Yang, Ying; Rupani, Asha; Bagnaninchi, Pierre; Wimpenny, Ian; Weightman, Alan

    2012-08-01

    The highly orientated collagen fibers in tendons play a critical role for transferring tensile stress, and they demonstrate birefringent optical properties. However, the influence that proteoglycans (PGs) have on the optical properties of tendons is yet to be fully elucidated. PGs are the essential components of the tendon extracellular matrix; the changes in their quantities and compositions have been associated with tendinopathies. In this study, polarization sensitive optical coherence tomography (PS-OCT) has been used to reveal the relationship between PG content/location and birefringence properties of tendons. Fresh chicken tendons were imaged at regular intervals by PS-OCT and polarization light microscopy during the extraction of PGs, using guanidine hydrochloride (GuHCl). Complementary time-lapsed images taken from the two modalities mutually demonstrated that the extraction of PGs disturbed the local organization of collagen bundles. This corresponded with a decrease in birefringence and associated banding pattern observed by PS-OCT. Furthermore, this study revealed there was a higher concentration of PGs in the outer sheath region than in the fascicles, and therefore the change in birefringence was reduced when extraction was performed on unsheathed tendons. The results provide new insights of tendon structure and the role of PGs on the structural stability of tendons, which also demonstrates the great potential for using PS-OCT as a diagnostic tool to examine tendon pathology.

  18. [Bone-tendon integration of autologous grafts using different diameter tunnels. An experimental study on sheep].

    Science.gov (United States)

    Sánchez Hidalgo, R; Forriol, F

    2012-01-01

    To analyse the bone-ligament integration «ligamentization» of the tendon graft in the reconstruction of anterior cruciate ligament (ACL) performing tunnels of different diameter. We performed the same reconstruction procedure using an autologous tendon graft taken from the superficial tendon of the hoof in 41 adult sheep. In Group A the tibial and femoral tunnels were 5 mm in diameter and in Group B they were 7 mm in diameter. The sheep were sacrificed at 3, 6 and 12 months after the surgery. Histological studies were performed on the graft and the tunnels, as well as a biomechanical analysis of the tibial-femoral complex. In group A we did not observe direct integration of the bone and the tendon graft or any fibres joining both structures, although there was vascularized fibrous tissue. In group B we did not observe any direct binding of the bone and the tendon graft either, although there was abundant fibrous tissue. The tendon graft showed a fascicular structure that increased over time in order to create septa for vascular penetration. Macroscopically the ACL graft had a dense appearance, which was very similar to the original tendon graft. The tendon grafts from group B and with a longer follow up period required a higher strength to produce maximum breakage than the tendon grafts from group A. After one year follow up, the histological study shows that the tendon graft is not transformed into a ligament, and there is no integration of the tendon graft in tunnels regardless of their diameter. Therefore, fixation techniques are essential to maintain the orientation and tension of the tendon graft. Copyright © 2011 SECOT. Published by Elsevier Espana. All rights reserved.

  19. Ultrasonographic assessment of flexor tendon mobilization: Effect of different protocols on tendon excursion

    NARCIS (Netherlands)

    J.-W.H. Korstanje (Jan-Wiebe); J. Soeters (Johannes); A.R. Schreuders (Ton); P.C. Amadio (Peter ); S.E.R. Hovius (Steven); H.J. Stam (Henk); R.W. Selles (Ruud)

    2012-01-01

    textabstractBackground: Different mobilization protocols have been proposed for rehabilitation after hand flexor tendon repair to provide tendon excursion sufficient to prevent adhesions. Several cadaver studies have shown that the position of the neighboring fingers influences tendon excursions of

  20. Does the adolescent patellar tendon respond to 5 days of cumulative load during a volleyball tournament?

    Science.gov (United States)

    van Ark, M; Docking, S I; van den Akker-Scheek, I; Rudavsky, A; Rio, E; Zwerver, J; Cook, J L

    2016-02-01

    Patellar tendinopathy (jumper's knee) has a high prevalence in jumping athletes. Excessive load on the patellar tendon through high volumes of training and competition is an important risk factor. Structural changes in the tendon are related to a higher risk of developing patellar tendinopathy. The critical tendon load that affects tendon structure is unknown. The aim of this study was to investigate patellar tendon structure on each day of a 5-day volleyball tournament in an adolescent population (16-18 years). The right patellar tendon of 41 players in the Australian Volleyball Schools Cup was scanned with ultrasound tissue characterization (UTC) on every day of the tournament (Monday to Friday). UTC can quantify structure of a tendon into four echo types based on the stability of the echo pattern. Generalized estimating equations (GEE) were used to test for change of echo type I and II over the tournament days. Participants played between eight and nine matches during the tournament. GEE analysis showed no significant change of echo type percentages of echo type I (Wald chi-square = 4.603, d.f. = 4, P = 0.331) and echo type II (Wald chi-square = 6.070, d.f. = 4, P = 0.194) over time. This study shows that patellar tendon structure of 16-18-year-old volleyball players is not affected during 5 days of cumulative loading during a volleyball tournament. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Does the adolescent patellar tendon respond to 5 days of cumulative load during a volleyball tournament?

    NARCIS (Netherlands)

    van Ark, Mathijs; Docking, Sean I.; van den Akker-Scheek, Inge; Rudavsky, A; Rio, Ebonie; Zwerver, Johannes; Cook, Jill L.

    Patellar tendinopathy (jumper's knee) has a high prevalence in jumping athletes. Excessive load on the patellar tendon through high volumes of training and competition is an important risk factor. Structural changes in the tendon are related to a higher risk of developing patellar tendinopathy. The

  2. The tendon approximator device in traumatic injuries.

    Science.gov (United States)

    Forootan, Kamal S; Karimi, Hamid; Forootan, Nazilla-Sadat S

    2015-01-01

    Precise and tension-free approximation of two tendon endings is the key predictor of outcomes following tendon lacerations and repairs. We evaluate the efficacy of a new tendon approximator device in tendon laceration repairs. In a comparative study, we used our new tendon approximator device in 99 consecutive patients with laceration of 266 tendons who attend a university hospital and evaluated the operative time to repair the tendons, surgeons' satisfaction as well as patient's outcomes in a long-term follow-up. Data were compared with the data of control patients undergoing tendon repair by conventional method. Totally 266 tendons were repaired by approximator device and 199 tendons by conventional technique. 78.7% of patients in first group were male and 21.2% were female. In approximator group 38% of patients had secondary repair of cut tendons and 62% had primary repair. Patients were followed for a mean period of 3years (14-60 months). Time required for repair of each tendon was significantly reduced with the approximator device (2 min vs. 5.5 min, ptendon repair were identical in the two groups and were not significantly different. 1% of tendons in group A and 1.2% in group B had rupture that was not significantly different. The new nerve approximator device is cheap, feasible to use and reduces the time of tendon repair with sustained outcomes comparable to the conventional methods.

  3. Evaluation of tissue displacement and regional strain in the Achilles tendon using quantitative high-frequency ultrasound.

    Science.gov (United States)

    Bogaerts, Stijn; De Brito Carvalho, Catarina; Scheys, Lennart; Desloovere, Kaat; D'hooge, Jan; Maes, Frederik; Suetens, Paul; Peers, Koen

    2017-01-01

    The Achilles tendon has a unique structure-function relationship thanks to its innate hierarchical architecture in combination with the rotational anatomy of the sub-tendons from the triceps surae muscles. Previous research has provided valuable insight in global Achilles tendon mechanics, but limitations with the technique used remain. Furthermore, given the global approach evaluating muscle-tendon junction to insertion, regional differences in tendon mechanical properties might be overlooked. However, recent advancements in the field of ultrasound imaging in combination with speckle tracking have made an intratendinous evaluation possible. This study uses high-frequency ultrasound to allow for quantification of regional tendon deformation. Also, an interactive application was developed to improve clinical applicability. A dynamic ultrasound of both Achilles tendons of ten asymptomatic subjects was taken. The displacement and regional strain in the superficial, middle and deep layer were evaluated during passive elongation and isometric contraction. Building on previous research, results showed that the Achilles tendon displaces non-uniformly with a higher displacement found in the deep layer of the tendon. Adding to this, a non-uniform regional strain behavior was found in the Achilles tendon during passive elongation, with the highest strain in the superficial layer. Further exploration of tendon mechanics will improve the knowledge on etiology of tendinopathy and provide options to optimize existing therapeutic loading programs.

  4. Tendon Length, Calf Muscle Atrophy, and Strength Deficit After Acute Achilles Tendon Rupture: Long-Term Follow-up of Patients in a Previous Study.

    Science.gov (United States)

    Heikkinen, Juuso; Lantto, Iikka; Piilonen, Juuso; Flinkkilä, Tapio; Ohtonen, Pasi; Siira, Pertti; Laine, Vesa; Niinimäki, Jaakko; Pajala, Ari; Leppilahti, Juhana

    2017-09-20

    In this prospective study, we used magnetic resonance imaging (MRI) to assess long-term Achilles tendon length, calf muscle volume, and muscle fatty degeneration after surgery for acute Achilles tendon rupture. From 1998 to 2001, 60 patients at our center underwent surgery for acute Achilles tendon rupture followed by early functional postoperative rehabilitation. Fifty-five patients were reexamined after a minimum duration of follow-up of 13 years (mean, 14 years), and 52 of them were included in the present study. Outcome measures included Achilles tendon length, calf muscle volume, and fatty degeneration measured with MRI of both the affected and the uninjured leg. The isokinetic plantar flexion strength of both calves was measured and was correlated with the structural findings. The Achilles tendon was, on average, 12 mm (95% confidence interval [CI] = 8.6 to 15.6 mm; p Achilles tendon length correlated substantially with the strength deficit (ρ = 0.51, p Achilles tendon length is associated with smaller calf muscle volumes and persistent plantar flexion strength deficits after surgical repair of Achilles tendon rupture. Strength deficits and muscle volume deficits are partly compensated for by FHL hypertrophy, but 11% to 13% deficits in soleus and gastrocnemius muscle volumes and 12% to 18% deficits in plantar flexion strength persist even after long-term follow-up. Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

  5. New insight in the architecture of the quadriceps tendon.

    Science.gov (United States)

    Grob, Karl; Manestar, Mirjana; Filgueira, Luis; Ackland, Timothy; Gilbey, Helen; Kuster, Markus S

    2016-12-01

    Published data regarding the structure of the quadriceps tendon are diverse. Dissection of the quadriceps muscle group revealed that beside the rectus femoris, vastus lateralis, vastus intermedius and vastus medialis a fifth muscle component- named the tensor vastus intermedius consistently fused into quadriceps tendon. It can be hypothesized that all these elements of the extensor apparatus of the knee joint must also be represented in the quadriceps tendon. This study investigated the multi-layered quadriceps tendon with special emphasis on all components of the quadriceps muscle group including the newly discovered tensor vastus intermedius. Ten cadaveric lower limbs were dissected. All muscle bellies of the extensor apparatus of the knee joint were identified and traced distally until they merged into the quadriceps tendon. Connections between the different aponeurotic layers of each muscle were studied from origin to insertion. The fusing points of each layer were marked. Their distance to the patella and the distances between the fusing points were measured. Six elements of the quadriceps muscle group form a tri-laminar structure of the quadriceps tendon. The intermediate layer could be further sub-divided. The elements of the quadriceps tendon are 1. lateral aponeurosis of the vastus intermedius, 2. deep and 3. superficial medial aponeurosis of the vastus intermedius, 4. vastus lateralis, 5. tensor vastus intermedius and 6. rectus femoris. Even with differences in fiber direction - these elements join each other a certain distance proximal to the patella. All elements were fused over a region measuring 13 to 90 mm proximal to the patella. Lateral parts of the vastus intermedius formed the deepest layer of the quadriceps tendon. The superficial and deep layer of the medial vastus intermedius aponeurosis fused 56 mm (range, 30 to 90 mm) and 33 mm (range, 13 to 53 mm) above the patella with the aponeurosis of the tensor vastus intermedius and vastus

  6. A cross-sectional study of the plantar flexor muscle and tendon during growth.

    Science.gov (United States)

    Kubo, K; Teshima, T; Hirose, N; Tsunoda, N

    2014-09-01

    The purpose of this study was to investigate growth changes in human plantar flexor muscle and tendons. In addition, we ascertained whether growth changes in muscle and tendon were more closely related to skeletal age than chronological age. 22 elementary school children (ESC), 19 junior high school students (JHS), and 23 young adults (ADT) men participated in this study. Maximal strain and hysteresis of tendon structures and cross-sectional area of Achilles tendon were measured using ultrasonography. In addition, skeletal age was assessed using Tanner-Whitehouse III method. Maximal strain of ESC was significantly greater than that of other groups, while no significant difference was observed between JHS and ADT. There was no difference in hysteresis among 3 groups. Relative cross-sectional area (to body mass(2/3)) of ADT was significantly smaller than that of other groups. For ESC and JHS, measured variables of muscle and tendon were significantly correlated to both chronological and skeletal ages. These results suggested that immature musculoskeletal system was protected by more extensible and larger tendon structures in ESC and only by larger tendon structures in JHS, respectively. Furthermore, there were no differences in correlation coefficient values between measured variables of muscle and tendon and chronological or skeletal ages. © Georg Thieme Verlag KG Stuttgart · New York.

  7. The Healing Effects of Aquatic Activities and Allogenic Injection of Platelet-Rich Plasma (PRP) on Injuries of Achilles Tendon in Experimental Rat.

    Science.gov (United States)

    Rajabi, Hamid; Sheikhani Shahin, Homa; Norouzian, Manijeh; Mehrabani, Davood; Dehghani Nazhvani, Seifollah

    2015-01-01

    Clinical tendon injuries represent serious and unresolved issues of the case on how the injured tendons could be improved based on natural structure and mechanical strength. The aim of this studies the effect of aquatic activities and alogenic platelet rich plasma (PRP) injection in healing Achilles tendons of rats. Forty rats were randomly divided into 5 equal groups. Seventy two hours after a crush lesion on Achilles tendon, group 1 underwent aquatic activity for 8 weeks (five sessions per week), group 2 received intra-articular PRP (1 ml), group 3 had aquatic activity together with injection PRP injection after an experimental tendon injury, group 4 did not receive any treatment after tendon injury and the control group with no tendon injuries. of 32 rats. After 8 weeks, the animals were sacrificed and the tendons were transferred in 10% formalin for histological evaluation. There was a significant increase in number of fibroblast and cellular density, and collagen deposition in group 3 comparing to other groups denoting to an effective healing in injured tendons. However, there was no significant difference among the studied groups based on their tendons diameter. Based on our findings on the number of fibroblast, cellular density, collagen deposition, and tendon diameter, it was shown that aquatic activity together with PRP injection was the therapeutic measure of choice enhance healing in tendon injuries that can open a window in treatment of damages to tendons.

  8. Tensile properties of a morphologically split supraspinatus tendon.

    Science.gov (United States)

    Matsuhashi, Tomoya; Hooke, Alexander W; Zhao, Kristin D; Goto, Akira; Sperling, John W; Steinmann, Scott P; An, Kai-Nan

    2014-07-01

    The supraspinatus tendon consists morphologically of two sub-regions, anterior and posterior. The anterior sub-region is thick and tubular while the posterior is thin and strap-like. The purpose of this study was to compare the structural and mechanical properties of the anterior and posterior sub-regions of the supraspinatus tendon. The supraspinatus tendons from seven human cadaveric shoulders were morphologically divided into the anterior and posterior sub-regions. Length, width, and thickness were measured. A servo-hydraulic testing machine (MTS Systems Corporation, Minneapolis, MN) was used for tensile testing. The maximal load at failure, modulus of elasticity and ultimate tendon stress were calculated. Repeated measures were used for statistical comparisons. The mean anterior tendon cross-sectional area was 47.3 mm(2) and the posterior was 32.1 mm(2) . Failure occurred most often at the insertion site: anterior (5/7) and posterior (6/7). All parameters of the anterior sub-region were significantly greater than those of the posterior sub-region. The moduli of elasticity at the insertion site were 592.4 MPa in the anterior sub-region and 217.7 MPa in the posterior (P = 0.01). The ultimate failure loads were 779.2 N in the anterior sub-region and 335.6 N in the posterior (P = 0.003). The ultimate stresses were 22.1 MPa in the anterior sub-region and 11.6 MPa in the posterior (P = 0.008). We recognized that the anterior and posterior sub-regions of the SSP tendon have significantly different mechanical properties. In a future study, we need to evaluate how best to repair an SSP tendon considering these region-specific properties. Copyright © 2013 Wiley Periodicals, Inc.

  9. Achilles tendon and sports; Die Achillessehne im Sport

    Energy Technology Data Exchange (ETDEWEB)

    Ulreich, N.; Kainberger, F. [Univ.-Klinik fuer Radiodiagnostik Wien (Austria); Huber, W.; Nehrer, S. [Univ.-Klinik fuer Orthopaedie Wien (Austria)

    2002-10-01

    Because of the rising popularity of recreational sports activities achillodynia is an often associated symptom with running, soccer and athletics. Therefore radiologist are frequently asked to image this tendon. The origin of the damage of the Achilles tendon is explained by numerous hypothesis, mainly a decreased perfusion and a mechanical irritation that lead to degeneration of the tendon. High-resolution technics such as sonography and magnetic resonance imaging show alterations in the structure of the tendon which can be graduated and classified. Manifestations like tendinosis, achillobursitis, rupture and Haglunds disease can summarized as the tendon overuse syndrom. A rupture of a tendon is mostly the result of a degeneration of the collagenfibres. The task of the radiologist is to acquire the intrinsic factors for a potential rupture. (orig.) [German] Aufgrund des starken Anstiegs des Freizeitsportes sind Achillodynien ein besonders mit Laufsport, Fussball und Leichtathletik assoziiertes Symptom und die Indikation zur radiologischen Abklaerung wird oft gestellt. Die Entstehung von Sehnenschaeden wird durch eine Reihe von Hypothesen erklaert, wobei eine gestoerte Gewebeperfusion und eine mechanische Irritation als Hauptursachen angesehen werden, die zur Degeneration des Sehnengewebes und des umgebenden Gleitlagers fuehren. Sie koennen aufgrund sonographischer und MR-tomographischer Zeichen meist klar klassifiziert und graduiert werden, wobei hochaufloesende Techniken eine wesentliche Voraussetzung fuer die subtile Analyse der Sehnenstruktur darstellen. Die einzelnen klinischen Erscheinungsformen wie Tendinose, Achillobursitis, Haglund-Ferse und Sehnenruptur koennen unter dem Begriff des ''Sehnenueberlastungssyndroms'' (Tendon overuse syndrome) subsummiert werden. Rupturen der Achillessehne treten so gut wie immer bei bereits vorgeschaedigtem Kollagenfasergewebe auf, und der radiologischen Diagnostik kommt wesentliche Bedeutung dabei zu

  10. Acute calcific tendinitis simulating tendon sheath infection.

    Science.gov (United States)

    Omololu, B; Alonge, T O; Ogunlade, S O

    2001-01-01

    Tendon sheath infection has catastrophic consequences if not diagnosed. We present acute calcific tendinitis, a simulator of tendon sheath infection with a good prognosis in a 14 year old athletic tennis player.

  11. Mechanical anchorage of FRP tendons – A literature review

    DEFF Research Database (Denmark)

    Schmidt, Jacob W.; Bennitz, Anders; Täljsten, Björn

    2012-01-01

    High tensile strength, good resistance to degradation and creep, low weight and, to some extent, the ability to change the modulus of elasticity are some of the advantages of using prestressed, unidirectional FRP (Fibre Reinforced Polymer) tendon systems. Bonded and non-bonded versions of these s......High tensile strength, good resistance to degradation and creep, low weight and, to some extent, the ability to change the modulus of elasticity are some of the advantages of using prestressed, unidirectional FRP (Fibre Reinforced Polymer) tendon systems. Bonded and non-bonded versions...... with such systems. This is especially important in external post-tensioned tendon systems, where the anchorage points are exposed to the full load throughout the life span of the structure. Consequently, there are large requirements related to the long-term capacity and fatigue resistance of such systems. Several...... anchorage systems for use with Aramid, Glass and Carbon FRP tendons have been proposed over the last two decades. Each system is usually tailored to a particular type of tendon. This paper presents a brief overview of bonded anchorage applications while the primary literature review discusses three methods...

  12. [Integration of the musculoskeletal components by tendons and ligaments.

    Science.gov (United States)

    Shukunami, Chisa

    Tendons transmit the mechanical force of skeletal muscle contraction to the bones, whereas ligaments connect the two bones together to stabilize the joint. During embryonic development, each component in the musculoskeletal system, initially develops as an individual primordium of tendon, ligament, skeletal muscle, and cartilage. Later, mutual interaction between these tissues plays an important role for the integration of the musculoskeletal components. Accumulating evidence suggests that myotendinous and osteotendinous/osteoligamentous junctions are important structures to maintain homeostasis of the integrated musculoskeletal components. In this review, we will focus on the establishment and maintenance of these junctions.

  13. A New Method for Modeling Spatial Prestressing Tendons

    Science.gov (United States)

    Li, Yi; Wang, Yuqian; Liu, Gao

    2010-05-01

    As a standard simulation procedure for curved lines and curved surfaces, spline has been widely used in the domain of computer-aided design. This paper presents a simple but relatively accurate procedure for the description of prestressing tendons. Cubic splines instead of conventional parabolic ones are introduced to obtain the characteristic parameters of the curved tendon profiles. The direct internal load method is adopted to obtain the equivalent load and loss of tendon force. In comparison with the traditional methods, Cubic splines needs less parameter for pre-processor and leads to higher accuracy in calculation. The direct internal load method can demonstrate the regularity of prestressing force acting on the structure, which modifies the prevalent equivalent load method. The results of the analysis presented in this paper indicate that the proposed method turns out to be convenient and reasonably accurate in the analysis of prestressed concrete bridges.

  14. Achilles tendon reflex measuring system

    Science.gov (United States)

    Szebeszczyk, Janina; Straszecka, Joanna

    1995-06-01

    The examination of Achilles tendon reflex is widely used as a simple, noninvasive clinical test in diagnosis and pharmacological therapy monitoring in such diseases as: hypothyroidism, hyperthyroidism, diabetic neuropathy, the lower limbs obstructive angiopathies and intermittent claudication. Presented Achilles tendon reflect measuring system is based on the piezoresistive sensor connected with the cylinder-piston system. To determinate the moment of Achilles tendon stimulation a detecting circuit was used. The outputs of the measuring system are connected to the PC-based data acquisition board. Experimental results showed that the measurement accuracy and repeatability is good enough for diagnostics and therapy monitoring purposes. A user friendly, easy-to-operate measurement system fulfills all the requirements related to recording, presentation and storing of the patients' reflexograms.

  15. Heel pain and Achilles tendonitis -- aftercare

    Science.gov (United States)

    ... About Your Injury The Achilles tendon connects your calf muscles to your heel bone. Together, they help ... running or jumping. Do activities that do not strain the tendon, such as ... and strengthen the muscles and tendon. Range of motion exercises will help ...

  16. Spontaneous Achilles tendon rupture in alkaptonuria | Mohammed ...

    African Journals Online (AJOL)

    Spontaneous Achilles tendon ruptures are uncommon. We present a 46-year-old man with spontaneous Achilles tendon rupture due to ochronosis. To our knowledge, this has not been previously reported in Sudan literature. The tendon of the reported patient healed well after debridement and primary repairs.

  17. A practical approach to magnetic resonance imaging of normal and injured tendons: pictorial essay

    Energy Technology Data Exchange (ETDEWEB)

    Forster, B.B. [UBC Hospital, Dept. of Radiology, Vancouver, British Columbia (Canada); Khan, K.M. [Univ. of British Columbia, Dept. of Family Practice, Vancouver, British Columbia (Canada)

    2003-10-01

    The imaging of tendon injury can be troublesome from a number of perspectives. First, tendon injuries are extremely common, accounting for 30%-50% of all sports injuries, and are, therefore, seen frequently at imaging centers. Second, tendons have a unique histology and ultra-structure with a number of normal variations that can mimic pathologic conditions, of which the radiologist should be aware. Finally, although full-thickness tears are easily diagnosed both clinically and with imaging, imaging findings for partial tears overlap those of tendinosis and those of normal tendons, and this can be very troublesome for radiologists, clinicians and patients alike. The objective of this article is to develop a practical approach to the magnetic resonance imaging (MRI) and analysis of tendons, both normal and pathologic, emphasizing the common features at different anatomic locations. (author)

  18. Patellar Tendon Rupture after Lateral Release without Predisposing Systemic Disease or Steroid Use

    Directory of Open Access Journals (Sweden)

    S. De Giorgi

    2015-01-01

    Full Text Available Arthroscopic technique for lateral release is the most widely used procedure for the correction of recurrent dislocations of the patella. In the relevant literature, several complications of lateral release are described, but the spontaneous patellar tendon rupture has never been suggested as a possible complication of this surgical procedure. Patellar tendon rupture is a rather infrequent and often unilateral lesion. Nevertheless, in case of systemic diseases (LES, rheumatoid arthritis, and chronic renal insufficiency that can weaken collagen structures, bilateral patellar tendon ruptures are described. We report a case of a 24-year-old girl with spontaneous rupture of patellar tendon who, at the age of 16, underwent an arthroscopic lateral release for recurrent dislocation of the patella. This is the first case of described spontaneous patellar tendon rupture that occurred some years after an arthroscopic lateral release.

  19. Tendon development and musculoskeletal assembly: emerging roles for the extracellular matrix

    Science.gov (United States)

    Subramanian, Arul; Schilling, Thomas F.

    2015-01-01

    Tendons and ligaments are extracellular matrix (ECM)-rich structures that interconnect muscles and bones. Recent work has shown how tendon fibroblasts (tenocytes) interact with muscles via the ECM to establish connectivity and strengthen attachments under tension. Similarly, ECM-dependent interactions between tenocytes and cartilage/bone ensure that tendon-bone attachments form with the appropriate strength for the force required. Recent studies have also established a close lineal relationship between tenocytes and skeletal progenitors, highlighting the fact that defects in signals modulated by the ECM can alter the balance between these fates, as occurs in calcifying tendinopathies associated with aging. The dynamic fine-tuning of tendon ECM composition and assembly thus gives rise to the remarkable characteristics of this unique tissue type. Here, we provide an overview of the functions of the ECM in tendon formation and maturation that attempts to integrate findings from developmental genetics with those of matrix biology. PMID:26672092

  20. Presence of lymphatics in a rat tendon lesion model.

    Science.gov (United States)

    Tempfer, Herbert; Kaser-Eichberger, Alexandra; Korntner, Stefanie; Lehner, Christine; Kunkel, Nadja; Traweger, Andreas; Trost, Andrea; Strohmaier, Clemens; Bogner, Barbara; Runge, Christian; Bruckner, Daniela; Krefft, Karolina; Heindl, Ludwig M; Reitsamer, Herbert A; Schrödl, Falk

    2015-04-01

    Tendons lack sufficient blood supply and represent a bradytroph tissue with prolonged healing time under pathological conditions. While the role of lymphatics in wound/defect healing in tissues with regular blood supply is well investigated, its involvement in tendon defects is not clear. We here try to identify the role of the lymphatic system in a tendon lesion model with morphological methods. A rat Achilles tendon lesion model (n = 5) was created via surgical intervention. Two weeks after surgery, animals were killed and lesioned site removed and prepared for polarization microscopy (picrosirius red) and immunohistochemistry using the lymphatic markers PROX1, VEGFR3, CCL21, LYVE-1, PDPN, and the vascular marker CD31. Additionally, DAPI was applied. Untreated tendons served as controls, confocal laser-scanning microscopy was used for documentation. At the lesion site, polarization microscopy revealed a structural reintegration while immunohistochemistry detected band-like profiles immunoreactive for PDPN, VEGFR3, CCL21, LYVE1, and CD31, surrounding DAPI-positive nuclei. PROX1-positive nuclei were detected within the lesion forming lines and opposed to each other. These PROX1-positive nuclei were surrounded by LYVE-1- or VEGFR3-positive surfaces. Few CD31-positive profiles contained PROX1-positive nuclei, while the majority of CD31-positive profiles lacked PROX1-positive nuclei. VEGFR3-, PDPN-, and LYVE-1-positive profiles were numerous within the lesion site, but absent in control tissue. Within 2 weeks, a structural rearrangement takes place in this lesion model, with dense lymphatic supply. The role of lymphatics in tendon wound healing is unclear, and proposed model represents a good possibility to study healing dynamics and lymphangiogenesis in a tissue almost completely lacking lymphatics in physiological conditions.

  1. Mechanoreceptors of the ligaments and tendons around the knee.

    Science.gov (United States)

    Çabuk, Haluk; Kuşku Çabuk, Fatmagül

    2016-09-01

    Proprioceptive inputs from the joints and limbs arise from mechanoreceptors in the muscles, ligaments and tendons. The knee joint has a wide range of movements, and proper neuroanatomical organization is critical for knee stability. Four ligaments (the anterior (ACL) and posterior (PCL) cruciate ligaments and the medial (MCL) and lateral (LCL) collateral ligaments) and four tendons (the semitendinosus (STT), gracilis (GT), popliteal (PoT), and patellar (PaT) tendons) from eight fresh frozen cadavers were harvested. Each harvested tissue was divided into its bone insertion side and its tendinous part for immunohistochemical examination using S100 staining. Freeman-Wyke's classification was used to identify the mechanoreceptors. The mechanoreceptors were usually located close to the bone insertion. Free nerve endings followed by Ruffini endings were the most common mechanoreceptors overall. No Pacini corpuscles were observed; free nerve endings and Golgi-like endings were most frequent in the PCL (PCL-PaT: P = 0.0.1, PCL-STT: P = 0.00), and Ruffini endings in the popliteal tendon (PoT-PaT: P = 0.00, Pot-STT: P = 0.00, PoT-LCL: P = 0.00, PoT-GT: P = 0.00, PoT-ACL: P = 0.09). The cruciate ligaments had more mechanoreceptors than the medial structures (MS) or the patellar tendon (CR-Pat: P = 0.000, CR-MS: P = 0.01). The differences in mechanoreceptor distributions between the ligaments and tendons could reflect the different roles of these structures in the dynamic coordination of knee motion. Clin. Anat. 29:789-795, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  2. Local administration of insulin-like growth factor-I (IGF-I) stimulates tendon collagen synthesis in humans

    DEFF Research Database (Denmark)

    Hansen, M; Boesen, A; Holm, L

    2013-01-01

    Collagen is the predominant structural protein in tendons and ligaments, and can be controlled by hormonal changes. In animals, injections of insulin-like growth factor I (IGF-I) has been shown to increase collagen synthesis in tendons and ligaments and to improve structural tissue healing...

  3. Sonography of Non-neoplastic Disorders of the Hand and Wrist Tendons.

    Science.gov (United States)

    Gitto, Salvatore; Draghi, Anna Guja; Draghi, Ferdinando

    2017-07-14

    Tendon disorders commonly cause hand and wrist disability and curtail the performance of work-related duties or routine tasks. Imaging is often needed for diagnosis, but it requires knowledge of the complex anatomic structures of the tendons of the hand and wrist as well as familiarity with related disorders. This review article aims to provide medical professionals with guidelines for the sonographic assessment of the tendons of hand and wrist and related disorders. Sonographic features of tendon disorders affecting the hand and wrist are described here, specifically: infectious tenosynovitis; tendon rupture or tearing; stenosing forms of tenosynovitis such as De Quervain disease and trigger finger; intersection syndrome; insertional tendinopathy; several forms of tendinous instability such as extensor carpi ulnaris instability, climber finger, and boxer knuckle; and tendinopathy in inflammatory rheumatic diseases. Postsurgical evaluation of the hand and wrist tendons is also discussed, including the healthy and pathologic appearances of operated tendons as well as impingement from orthopedic hardware. In conclusion, sonography is effective in assessing the tendons of the hand and wrist and related disorders and represents a valuable tool for diagnosis. © 2017 by the American Institute of Ultrasound in Medicine.

  4. Adipose derived stromal vascular fraction improves early tendon healing: an experimental study in rabbits

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    Mehdi Behfar

    2011-11-01

    Full Text Available Tendon never restores the complete biological and mechanical properties after healing. Bone marrow and recently adipose tissue have been used as the sources of mesenchymal stem cells, which have been proven to enhance tendon healing. Stromal vascular fraction (SVF, derived from adipose tissue by an enzymatic digestion, represents an alternative source of multipotent cells, which undergo differentiation into multiple lineages to be used in regenerative medicine. In the present study, we investigated potentials of this source on tendon healing. Twenty rabbits were divided into control and treatment groups. Five rabbits were used as donors of adipose tissue. The injury model was unilateral complete transection through the middle one third of deep digital flexor tendon. Immediately after suture repair, either fresh stromal vascular fraction from enzymatic digestion of adipose tissue or placebo was intratendinously injected into the suture site in treatments and controls, respectively. Cast immobilization was continued for two weeks after surgery. Animals were sacrificed at the third week and tendons underwent histological, immunohistochemical, and mechanical evaluations. By histology, improved fibrillar organization and remodeling of neotendon were observed in treatment group. Immunohistochemistry revealed an insignificant increase in collagen type III and I expression in treatments over controls. Mechanical testing showed significant increase in maximum load and energy absorption in SVF treated tendons. The present study showed that intratendinous injection of uncultured adipose derived stromal vascular fraction improved structural and mechanical properties of repaired tendon and it could be an effective modality for treating tendon laceration.

  5. The role of the non-collagenous matrix in tendon function

    Science.gov (United States)

    Thorpe, Chavaunne T; Birch, Helen L; Clegg, Peter D; Screen, Hazel RC

    2013-01-01

    Tendon consists of highly ordered type I collagen molecules that are grouped together to form subunits of increasing diameter. At each hierarchical level, the type I collagen is interspersed with a predominantly non-collagenous matrix (NCM) (Connect. Tissue Res., 6, 1978, 11). Whilst many studies have investigated the structure, organization and function of the collagenous matrix within tendon, relatively few have studied the non-collagenous components. However, there is a growing body of research suggesting the NCM plays an important role within tendon; adaptations to this matrix may confer the specific properties required by tendons with different functions. Furthermore, age-related alterations to non-collagenous proteins have been identified, which may affect tendon resistance to injury. This review focuses on the NCM within the tensional region of developing and mature tendon, discussing the current knowledge and identifying areas that require further study to fully understand structure–function relationships within tendon. This information will aid in the development of appropriate techniques for tendon injury prevention and treatment. PMID:23718692

  6. Chronic Achilles tendon rupture reconstructed using hamstring tendon autograft.

    Science.gov (United States)

    Ellison, Philip; Mason, Lyndon William; Molloy, Andrew

    2016-03-01

    Chronic rupture of the Achilles tendon (delayed diagnosis of more than 4 weeks) can result in retraction of the tendon and inadequate healing. Direct repair may not be possible and augmentation methods are challenging when the defect exceeds 5-6 cm, especially if the distal stump is grossly tendinopathic. We describe our method of Achilles tendon reconstruction with ipsilateral semitendinosis autograft and interference screw fixation in a patient with chronic rupture, a 9 cm defect and gross distal tendinopathy. Patient reported outcome measures consistently demonstrated improved health status at 12 months post surgery: MOXFQ-Index 38-25, EQ5D-5L 18-9, EQ VAS 70-90 and VISA-A 1-64. The patient was back to full daily function, could single leg heel raise and was gradually returning to sport. No complications or adverse events were recorded. Reconstruction of chronic tears of the Achilles tendon with large defects and gross tendinopathy using an ipsilateral semitendinosis autograft and interference screw fixation can achieve satisfactory improvements in patient reported outcomes up to 1 year post-surgery. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Nutrition of flexor tendons in monkeys.

    Science.gov (United States)

    Manske, P R; Bridwell, K; Whiteside, L A; Lesker, P A

    1978-10-01

    The hydrogen washout technique was used to investigate the role of synovial diffusion versus vascular perfusion in the nutrition of monkey flexor tendons within the digital sheath. There was no significant difference in the uptake and washout of hydrogen tracer by tendons in contact with synovium but detached from the surrounding vasculature, compared to control tendons. However, there was insignificant uptake of tracer by tendons with intact vasculature, but separated from synovium. Synovial diffusion is a primary nutrient pathway of monkey flexor tendons within the digital sheath.

  8. Can PRP effectively treat injured tendons?

    Science.gov (United States)

    Wang, James H-C

    2014-01-01

    PRP is widely used to treat tendon and other tissue injuries in orthopaedics and sports medicine; however, the efficacy of PRP treatment on injured tendons is highly controversial. In this commentary, I reason that there are many PRP- and patient-related factors that influence the outcomes of PRP treatment on injured tendons. Therefore, more basic science studies are needed to understand the mechanism of PRP on injured tendons. Finally, I suggest that better understanding of the PRP action mechanism will lead to better use of PRP for the effective treatment of tendon injuries in clinics.

  9. Bioreactor Design for Tendon/Ligament Engineering

    Science.gov (United States)

    Wang, Tao; Gardiner, Bruce S.; Lin, Zhen; Rubenson, Jonas; Kirk, Thomas B.; Wang, Allan; Xu, Jiake

    2013-01-01

    Tendon and ligament injury is a worldwide health problem, but the treatment options remain limited. Tendon and ligament engineering might provide an alternative tissue source for the surgical replacement of injured tendon. A bioreactor provides a controllable environment enabling the systematic study of specific biological, biochemical, and biomechanical requirements to design and manufacture engineered tendon/ligament tissue. Furthermore, the tendon/ligament bioreactor system can provide a suitable culture environment, which mimics the dynamics of the in vivo environment for tendon/ligament maturation. For clinical settings, bioreactors also have the advantages of less-contamination risk, high reproducibility of cell propagation by minimizing manual operation, and a consistent end product. In this review, we identify the key components, design preferences, and criteria that are required for the development of an ideal bioreactor for engineering tendons and ligaments. PMID:23072472

  10. Transcription factor EGR1 directs tendon differentiation and promotes tendon repair

    Science.gov (United States)

    Guerquin, Marie-Justine; Charvet, Benjamin; Nourissat, Geoffroy; Havis, Emmanuelle; Ronsin, Olivier; Bonnin, Marie-Ange; Ruggiu, Mathilde; Olivera-Martinez, Isabel; Robert, Nicolas; Lu, Yinhui; Kadler, Karl E.; Baumberger, Tristan; Doursounian, Levon; Berenbaum, Francis; Duprez, Delphine

    2013-01-01

    Tendon formation and repair rely on specific combinations of transcription factors, growth factors, and mechanical parameters that regulate the production and spatial organization of type I collagen. Here, we investigated the function of the zinc finger transcription factor EGR1 in tendon formation, healing, and repair using rodent animal models and mesenchymal stem cells (MSCs). Adult tendons of Egr1–/– mice displayed a deficiency in the expression of tendon genes, including Scx, Col1a1, and Col1a2, and were mechanically weaker compared with their WT littermates. EGR1 was recruited to the Col1a1 and Col2a1 promoters in postnatal mouse tendons in vivo. Egr1 was required for the normal gene response following tendon injury in a mouse model of Achilles tendon healing. Forced Egr1 expression programmed MSCs toward the tendon lineage and promoted the formation of in vitro–engineered tendons from MSCs. The application of EGR1-producing MSCs increased the formation of tendon-like tissues in a rat model of Achilles tendon injury. We provide evidence that the ability of EGR1 to promote tendon differentiation is partially mediated by TGF-β2. This study demonstrates EGR1 involvement in adult tendon formation, healing, and repair and identifies Egr1 as a putative target in tendon repair strategies. PMID:23863709

  11. Multiple extensor tendons reconstruction with hamstring tendon grafts and flap coverage for severe dorsal hand injuries.

    Science.gov (United States)

    Ozbaydar, M; Orman, O; Ozel, O; Altan, E

    2017-10-10

    Treatment of patients with traumatic loss of skin and multiple extensor tendons on the dorsum of the hand is a challenge. The aim of this study was to assess the outcome after reconstruction of soft tissues and multiple extensor tendons in patients who suffered traumatic loss of skin and multiple extensor tendons. Ten patients were enrolled in the study. These patients underwent single-stage reconstruction with autogenous hamstring tendon grafts for multiple extensor tendon defects and fasciocutaneous flaps for coverage of dorsal hand defects. In total, 25 tendons (2 tendons in 5 patients and 3 tendons in 5 patients) were reconstructed. The semitendinosus tendon was used in all patients and the gracilis tendon was added in five patients for tendon reconstruction. Total tendon length requiring reconstruction was between 9cm and 31cm. Free anterolateral thigh flaps were used in six patients and reverse pedicled forearm flaps were used in four patients. According to Miller's scoring system, 8 fingers had excellent results, 12 fingers had good results and 5 fingers had fair results at the final follow-up. Hamstring tendons can be used satisfactorily for primary reconstruction of multiple digital extensor tendons due to their availability and compatibility, with a fasciocutaneous flap. IV. Copyright © 2017 SFCM. Published by Elsevier Masson SAS. All rights reserved.

  12. Hyperuricemic PRP in Tendon Cells

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    I. Andia

    2014-01-01

    Full Text Available Platelet-rich plasma (PRP is injected within tendons to stimulate healing. Metabolic alterations such as the metabolic syndrome, diabetes, or hyperuricemia could hinder the therapeutic effect of PRP. We hypothesise that tendon cells sense high levels of uric acid and this could modify their response to PRP. Tendon cells were treated with allogeneic PRPs for 96 hours. Hyperuricemic PRP did not hinder the proliferative actions of PRP. The gene expression pattern of inflammatory molecules in response to PRP showed absence of IL-1b and COX1 and modest expression of IL6, IL8, COX2, and TGF-b1. IL8 and IL6 proteins were secreted by tendon cells treated with PRP. The synthesis of IL6 and IL8 proteins induced by PRP is decreased significantly in the presence of hyperuricemia (P = 0.017 and P = 0.012, resp.. Concerning extracellular matrix, PRP-treated tendon cells displayed high type-1 collagen, moderate type-3 collagen, decorin, and hyaluronan synthase-2 expression and modest expression of scleraxis. Hyperuricemia modified the expression pattern of extracellular matrix proteins, upregulating COL1 (P = 0.036 and COMP (P = 0.012 and downregulating HAS2 (P = 0.012. Positive correlations between TGF-b1 and type-1 collagen (R = 0.905, P = 0.002 and aggrecan (R = 0.833, P = 0.010 and negative correlations between TGF-b1 and IL6 synthesis (R = −0.857, P = 0.007 and COX2 (R = −0.810, P = 0.015 were found.

  13. Ultrasound elasticity imaging of human posterior tibial tendon

    Science.gov (United States)

    Gao, Liang

    Posterior tibial tendon dysfunction (PTTD) is a common degenerative condition leading to a severe impairment of gait. There is currently no effective method to determine whether a patient with advanced PTTD would benefit from several months of bracing and physical therapy or ultimately require surgery. Tendon degeneration is closely associated with irreversible degradation of its collagen structure, leading to changes to its mechanical properties. If these properties could be monitored in vivo, it could be used to quantify the severity of tendonosis and help determine the appropriate treatment. Ultrasound elasticity imaging (UEI) is a real-time, noninvasive technique to objectively measure mechanical properties in soft tissue. It consists of acquiring a sequence of ultrasound frames and applying speckle tracking to estimate displacement and strain at each pixel. The goals of my dissertation were to 1) use acoustic simulations to investigate the performance of UEI during tendon deformation with different geometries; 2) develop and validate UEI as a potentially noninvasive technique for quantifying tendon mechanical properties in human cadaver experiments; 3) design a platform for UEI to measure mechanical properties of the PTT in vivo and determine whether there are detectable and quantifiable differences between healthy and diseased tendons. First, ultrasound simulations of tendon deformation were performed using an acoustic modeling program. The effects of different tendon geometries (cylinder and curved cylinder) on the performance of UEI were investigated. Modeling results indicated that UEI accurately estimated the strain in the cylinder geometry, but underestimated in the curved cylinder. The simulation also predicted that the out-of-the-plane motion of the PTT would cause a non-uniform strain pattern within incompressible homogeneous isotropic material. However, to average within a small region of interest determined by principal component analysis (PCA

  14. The study of optical properties and proteoglycan content of tendons by PS-OCT

    Science.gov (United States)

    Yang, Ying; Rupani, Asha; Weightman, Alan; Wimpenny, Ian; Bagnaninchi, Pierre; Ahearne, Mark

    2011-03-01

    Tendons are load-bearing collagenous tissues consisting mainly of type I collagen and various proteoglycans (PGs) including decorin and versican. It is widely accepted that highly orientated collagen fibers in tendons a play critical role for transferring tensile stress and demonstrate birefringent optical properties. However, the influence that proteoglycans have on the optical properties of tendons is yet to be fully elucidated. Tendinopathy (defined as a syndrome of tendon pain, tenderness and swelling that affects the normal function of the tissue) is a common disease associated with sporting injuries or degeneration. PG's are the essential components of the tendon extracellular matrix; changes in their quantities and compositions have been associated with tendinopathy. In this study, polarization sensitive optical coherence tomography (PS-OCT) has been used to reveal the relationship between proteoglycan content/location and birefringent properties of tendons. Tendons dissected from freshly slaughtered chickens were imaged at regular intervals by PS-OCT and polarizing light microscope during the extraction of PGs or glycosaminoglycans using established protocols (guanidine hydrochloride (GuHCl) or proteinase K solution). The macroscopic and microscopic time lapsed images are complimentary; mutually demonstrating that there was a higher concentration of PG's in the outer sheath region than in the fascicles; and the integrity of the sheath affected extraction process and the OCT birefringence bands. Extraction of PGs using GuHCl disturbed the organization of local collagen bundles, which corresponded to a reduction in the frequency of birefringence bands and the band width by PS-OCT. The feature of OCT penetration depth helped us to define the heterogeneous distribution of PG's in tendon, which was complimented by polarizing light microscopy. The results provide new insight of tendon structure and also demonstrate a great potential for using PS-OCT as a

  15. Extracellular matrix adaptation of tendon and skeletal muscle to exercise

    DEFF Research Database (Denmark)

    Kjaer, Michael; Magnusson, Peter; Krogsgaard, Michael

    2006-01-01

    The extracellular matrix (ECM) of connective tissues enables linking to other tissues, and plays a key role in force transmission and tissue structure maintenance in tendons, ligaments, bone and muscle. ECM turnover is influenced by physical activity, and both collagen synthesis and metalloprotea...... is supported by findings of gender-related differences in the activation of collagen synthesis with exercise. These findings may provide the basis for understanding tissue overloading and injury in both tendons and skeletal muscle.......The extracellular matrix (ECM) of connective tissues enables linking to other tissues, and plays a key role in force transmission and tissue structure maintenance in tendons, ligaments, bone and muscle. ECM turnover is influenced by physical activity, and both collagen synthesis and metalloprotease...... is regulated by cyclooxygenase-2 (COX-2)-mediated pathways, and glucose uptake is regulated by specific pathways in tendons that differ from those in skeletal muscle. Chronic loading in the form of physical training leads both to increased collagen turnover as well as to some degree of net collagen synthesis...

  16. Mechanical properties of the human Achilles tendon, in vivo

    DEFF Research Database (Denmark)

    Kongsgaard, M; Nielsen, C H; Hegnsvad, S

    2011-01-01

    Ultrasonography has been widely applied for in vivo measurements of tendon mechanical properties. Assessments of human Achilles tendon mechanical properties have received great interest. Achilles tendon injuries predominantly occur in the tendon region between the Achilles-soleus myotendinous...... Achilles tendon in vivo by the use of ultrasonography and 2) assess the between-day reproducibility of these measurements....

  17. [Diagnosis of flexor tendon injuries of the hand].

    Science.gov (United States)

    Hahn, P; Unglaub, F; Spies, C K

    2015-10-01

    Open or closed flexor tendon injuries may be caused by a variety of circumstances. Loss of function based on flexor tendon injuries is quite often missed. Therefore, a precise knowledge of the anatomy, the biomechanical behaviour of tendons and the intrinsic hand muscles enables the clinician to examine flexor tendon injuries adequately. This article focuses on relevant clinical tests for flexor tendon injuries.

  18. Tendon healing in vivo. An experimental model.

    Science.gov (United States)

    Abrahamsson, S O; Lundborg, G; Lohmander, L S

    1989-01-01

    Flexor tendon segments were incubated in a diffusion chamber in the subcutis of rabbits. Tendons incubated up to 6 weeks in the diffusion chamber showed proliferating and migrating cells from the epitenon cell layer as well as viable endotenon cells. Explants frozen in liquid nitrogen prior to incubation showed no signs of extrinsic cell contamination and remained non-viable indicating that no cell penetration occurred through the Millipore filter and that cell division seen in non-frozen and incubated tendons was an expression of intrinsic cellular proliferative capacity of the tendon. In tendon segments incubated in chambers for three weeks, collagen synthesis was reduced by 50% and the rate of cell proliferation measured as 3H-thymidine incorporation, was 15 times that of native tendons. Frozen and incubated tendons showed only traces of remaining matrix synthesis or cell proliferation. With this experimental model we have histologically and biochemically shown that tendons may survive and heal while the nutrition exclusively could be based on diffusion and the tendons have an intrinsic capacity of healing. The described model enables further studies on tendon healing and its regulation.

  19. Ipsilateral free semitendinosus tendon graft transfer for reconstruction of chronic tears of the Achilles tendon

    Directory of Open Access Journals (Sweden)

    Gougoulias Nikolaos

    2008-07-01

    Full Text Available Abstract Background Many techniques have been developed for the reconstruction of the Achilles tendon in chronic tears. In presence of a large gap (greater than 6 centimetres, tendon augmentation is required. Methods We present our method of minimally invasive semitendinosus reconstruction for the Achilles tendon using one para-midline and one midline incision. Results The first incision is a 5 cm longitudinal incision, made 2 cm proximal and just medial to the palpable end of the residual tendon. The second incision is 3 cm long and is also longitudinal but is 2 cm distal and in the midline to the distal end of the tendon rupture. The distal and proximal Achilles tendon stumps are mobilised. After trying to reduce the gap of the ruptured Achilles tendon, if the gap produced is greater than 6 cm despite maximal plantar flexion of the ankle and traction on the Achilles tendon stumps, the ipsilateral semitendinosus tendon is harvested. The semitendinosus tendon is passed through small incisions in the substance of the proximal stump of the Achilles tendon, and it is sutured to the Achilles tendon. It is then passed beneath the intact skin bridge into the distal incision, and passed from medial to lateral through a transverse tenotomy in the distal stump. With the ankle in maximal plantar flexion, the semitendinosus tendon is sutured to the Achilles tendon at each entry and exit point Conclusion This minimally invasive technique allows reconstruction of the Achilles tendon using the tendon of semitendinosus preserving skin integrity over the site most prone to wound breakdown, and can be especially used to reconstruct the Achilles tendon in the presence of large gap (greater than 6 centimetres.

  20. Successful Nonoperative Treatment of Isolated Popliteus Tendon Avulsion Fractures in Two Adolescents

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    Scott D. McKay

    2014-01-01

    Full Text Available Isolated popliteal tendon avulsion fractures are relatively uncommon in the pediatric population as other posterolateral lateral structures are often involved. This report describes two skeletally immature male patients who presented with knee injuries without ligamentous instability and were subsequently diagnosed with isolated popliteus tendon avulsion fractures. Both of these patients were managed nonoperatively and had subjectively full recoveries. As the treatment for isolated popliteal tendon avulsion fractures is still unclear, the report here may contribute to strategies regarding conservative treatment of these injuries.

  1. The effect of estrogen on tendon and ligament metabolism and function.

    Science.gov (United States)

    Leblanc, D R; Schneider, M; Angele, P; Vollmer, G; Docheva, D

    2017-09-01

    Tendons and ligaments are crucial structures inside the musculoskeletal system. Still many issues in the treatment of tendon diseases and injuries have yet not been resolved sufficiently. In particular, the role of estrogen-like compound (ELC) in tendon biology has received until now little attention in modern research, despite ELC being a well-studied and important factor in the physiology of other parts of the musculoskeletal system. In this review we attempt to summarize the available information on this topic and to determine many open questions in this field. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  2. The effects of immobilization on the mechanical properties of the patellar tendon in younger and older men

    DEFF Research Database (Denmark)

    Couppé, C; Suetta, C; Kongsgaard, M

    2012-01-01

    It remains unknown if inactivity changes the mechanical properties of the human patellar tendon in younger and older healthy persons. The purpose was to examine the effects of short-term unilateral immobilization on the structural and mechanical properties of the patellar tendon in older men and ...

  3. Active Achilles tendon kinesitherapy accelerates Achilles tendon repair by promoting neurite regeneration☆

    Science.gov (United States)

    Jielile, Jiasharete; Aibai, Minawa; Sabirhazi, Gulnur; Shawutali, Nuerai; Tangkejie, Wulanbai; Badelhan, Aynaz; Nuerduola, Yeermike; Satewalede, Turde; Buranbai, Darehan; Hunapia, Beicen; Jialihasi, Ayidaer; Bai, Jingping; Kizaibek, Murat

    2012-01-01

    Active Achilles tendon kinesitherapy facilitates the functional recovery of a ruptured Achilles tendon. However, protein expression during the healing process remains a controversial issue. New Zealand rabbits, aged 14 weeks, underwent tenotomy followed immediately by Achilles tendon microsurgery to repair the Achilles tendon rupture. The tendon was then immobilized or subjected to postoperative early motion treatment (kinesitherapy). Mass spectrography results showed that after 14 days of motion treatment, 18 protein spots were differentially expressed, among which, 12 were up-regulated, consisting of gelsolin isoform b and neurite growth-related protein collapsing response mediator protein 2. Western blot analysis showed that gelsolin isoform b was up-regulated at days 7–21 of motion treatment. These findings suggest that active Achilles tendon kinesitherapy promotes the neurite regeneration of a ruptured Achilles tendon and gelsolin isoform b can be used as a biomarker for Achilles tendon healing after kinesitherapy. PMID:25317130

  4. Biceps tendon disorders in athletes.

    Science.gov (United States)

    Eakin, C L; Faber, K J; Hawkins, R J; Hovis, W D

    1999-01-01

    It has been proposed that the long head of the biceps functions as a humeral head depressor and stabilizer. In addition, in many overhead sports, the biceps helps to accelerate and decelerate the arm. With improper training or fatigue, inordinate stresses can be placed on the biceps as it attempts to compensate for other muscles. This can lead to attrition and failure, either within the tendon substance or at its origin. Bicipital problems in athletes usually occur in conjunction with other types of shoulder disorders, such as rotator cuff impingement and glenohumeral instability, making determination of the role and degree of biceps involvement difficult. Conditions affecting the biceps tendon in athletes can be generally classified as degeneration, instability, and disorders of the origin. Because of the close association of biceps lesions with other abnormalities, a thorough evaluation of the shoulder with a suspected biceps disorder is essential. Treatment of bicipital problems in athletes must often be accompanied by treatment of associated shoulder conditions.

  5. A Fibre-Reinforced Poroviscoelastic Model Accurately Describes the Biomechanical Behaviour of the Rat Achilles Tendon

    Science.gov (United States)

    Heuijerjans, Ashley; Matikainen, Marko K.; Julkunen, Petro; Eliasson, Pernilla; Aspenberg, Per; Isaksson, Hanna

    2015-01-01

    Background Computational models of Achilles tendons can help understanding how healthy tendons are affected by repetitive loading and how the different tissue constituents contribute to the tendon’s biomechanical response. However, available models of Achilles tendon are limited in their description of the hierarchical multi-structural composition of the tissue. This study hypothesised that a poroviscoelastic fibre-reinforced model, previously successful in capturing cartilage biomechanical behaviour, can depict the biomechanical behaviour of the rat Achilles tendon found experimentally. Materials and Methods We developed a new material model of the Achilles tendon, which considers the tendon’s main constituents namely: water, proteoglycan matrix and collagen fibres. A hyperelastic formulation of the proteoglycan matrix enabled computations of large deformations of the tendon, and collagen fibres were modelled as viscoelastic. Specimen-specific finite element models were created of 9 rat Achilles tendons from an animal experiment and simulations were carried out following a repetitive tensile loading protocol. The material model parameters were calibrated against data from the rats by minimising the root mean squared error (RMS) between experimental force data and model output. Results and Conclusions All specimen models were successfully fitted to experimental data with high accuracy (RMS 0.42-1.02). Additional simulations predicted more compliant and soft tendon behaviour at reduced strain-rates compared to higher strain-rates that produce a stiff and brittle tendon response. Stress-relaxation simulations exhibited strain-dependent stress-relaxation behaviour where larger strains produced slower relaxation rates compared to smaller strain levels. Our simulations showed that the collagen fibres in the Achilles tendon are the main load-bearing component during tensile loading, where the orientation of the collagen fibres plays an important role for the tendon

  6. Nutrient pathways of flexor tendons in primates.

    Science.gov (United States)

    Manske, P R; Lesker, P A

    1982-09-01

    The perfusion and diffusion pathways to the flexor profundus tendons of 40 monkeys were investigated by measuring the uptake of tritiated proline by various tendon segments. In the absence of all vascular connections, the process of diffusion provides nutrients to all areas of flexor tendon and in this study the process of diffusion was greater. The distal segment of tendon was observed to be profused most rapidly. The proximal tendon segment is perfused from both the muscular-tendinous junction and the vinculum longus; vincular segment perfusion is via the vinculum longus vessels alone; central segment perfusion is shared by the vinculum longus and vinculum brevis vasculature. The distal segment uptake is by both the process of diffusion or vinculum brevis perfusion. The osseous attachment at the distal phalanx contributes little to tendon nutrition.

  7. Nutrient pathways of flexor tendons in primates

    Energy Technology Data Exchange (ETDEWEB)

    Manske, P.R.; Lesker, P.A.

    1982-09-01

    The perfusion and diffusion pathways to the flexor profundus tendons of 40 monkeys were investigated by measuring the uptake of tritiated proline by various tendon segments. In the absence of all vascular connections, the process of diffusion provides nutrients to all areas of flexor tendon and in this study the process of diffusion was greater. The distal segment of tendon was observed to be profused most rapidly. The proximal tendon segment is perfused from both the muscular-tendinous junction and the vinculum longus; vincular segment perfusion is via the vinculum longus vessels alone; central segment perfusion is shared by the vinculum longus and vinculum brevis vasculature. The distal segment uptake is by both the process of diffusion or vinculum brevis perfusion. The osseous attachment at the distal phalanx contributes little to tendon nutrition.

  8. Biochemical, histological, and biomechanical analyses of canine tendon.

    Science.gov (United States)

    Okuda, Y; Gorski, J P; An, K N; Amadio, P C

    1987-01-01

    To define the matrix composition and architecture of canine flexor tendon, and to correlate tissue structure with applied mechanical loading, five anatomical regions of flexor tendon were studied. Histologically, two prominent fibrocartilaginous areas were observed on concave aspects of the tendon. The location of the major fibrocartilaginous area at the metacarpophalangeal joint correlated well with the region predicted by biomechanical modeling to be under greatest compressive loads during standing and claw movement. Comparative biochemical analysis showed an elevated water content, a five-fold higher hexuronic acid content, and a larger hydroxylysine/hydroxyproline ratio in this region relative to that for more tendinous areas. The major glycosaminoglycan component of fibrocartilaginous areas was chondroitin sulfate, whereas in other areas dermatan sulfate and hyaluronic acid dominated. Cell density and DNA analyses indicated a slightly higher cellularity for fibrocartilaginous areas and the region of vinculum insertion. These data document the existence of discrete areas of specialization within the flexor tendon that appear to be an adaptation to nutritional and mechanical factors.

  9. Achilles tendon rupture in badminton.

    Science.gov (United States)

    Kaalund, S; Lass, P; Høgsaa, B; Nøhr, M

    1989-01-01

    The typical badminton player with an Achilles tendon rupture is 36 years old and, despite limbering up, is injured at the rear line in a sudden forward movement. He resumes work within three months and has a slight lack of dorsiflexion in the ankle as the main complication. Most patients resume badminton within one year, but some finish their sports career, mainly due to fear of a new injury. The investigation discusses predisposing factors and prophylactic measures. PMID:2605439

  10. Investigating tendon mineralisation in the avian hindlimb: a model for tendon ageing, injury and disease

    Science.gov (United States)

    Agabalyan, Natacha A; Evans, Darrell J R; Stanley, Rachael L

    2013-01-01

    Mineralisation of the tendon tissue has been described in various models of injury, ageing and disease. Often resulting in painful and debilitating conditions, the processes underlying this mechanism are poorly understood. To elucidate the progression from healthy tendon to mineralised tendon, an appropriate model is required. In this study, we describe the spontaneous and non-pathological ossification and calcification of tendons of the hindlimb of the domestic chicken (Gallus gallus domesticus). The appearance of the ossified avian tendon has been described previously, although there have been no studies investigating the developmental processes and underlying mechanisms leading to the ossified avian tendon. The tissue and cells from three tendons – the ossifying extensor and flexor digitorum longus tendons and the non-ossifying Achilles tendon – were analysed for markers of ageing and mineralisation using histology, immunohistochemistry, cytochemistry and molecular analysis. Histologically, the adult tissue showed a loss of healthy tendon crimp morphology as well as markers of calcium deposits and mineralisation. The tissue showed a lowered expression of collagens inherent to the tendon extracellular matrix and presented proteins expressed by bone. The cells from the ossified tendons showed a chondrogenic and osteogenic phenotype as well as tenogenic phenotype and expressed the same markers of ossification and calcification as the tissue. A molecular analysis of the gene expression of the cells confirmed these results. Tendon ossification within the ossified avian tendon seems to be the result of an endochondral process driven by its cells, although the roles of the different cell populations have yet to be elucidated. Understanding the role of the tenocyte within this tissue and the process behind tendon ossification may help us prevent or treat ossification that occurs in injured, ageing or diseased tendon. PMID:23826786

  11. Transcutaneous medial canthal tendon incision to the medial orbit.

    Science.gov (United States)

    Timoney, Peter J; Sokol, Jason A; Hauck, Matthew J; Lee, H B Harold; Nunery, William R

    2012-01-01

    The surgical approach to the medial orbit allows superior exposure of the medial orbital wall and nasal bones, extending to the orbital apex, with excellent cosmetic results. This is a retrospective database study of all patients (N = 98) undergoing a transcutaneous medial canthal tendon incision in practice during 2009. This 1.5- to 2.0-cm incision is made just anterior to, in the same plane as, and shaving the anterior ramus of the medial canthal tendon. After exposing the origin of the anterior ramus of the medial canthal tendon, the periorbita along with the attached medial canthal tendon is elevated, exposing the entire medial orbital wall from the orbital strut to the trochlea. Anterior dissection allows access to the nasal bones to the dorsum of the nasal bridge. The parameters studied in this report were the complication rates (including scarring requiring revision, telecanthus, diplopia related to the technique, and injury to the optic nerve or other orbital structures) and photographic evidence of the final cosmetic result of this approach. During 2009, 173 surgical procedures were performed through the transcutaneous medial canthal tendon incision. The procedures comprised 89 fracture repairs of the nasal or ethmoid complex, 2 naso-orbito-ethmoid fracture repairs, 4 cases of isolated nasal fracture repair, 37 medial wall decompressions for ophthalmic Graves disease, 13 cases of subperiosteal abscess drainage, and 28 dacyrocystorhinostomies using a slightly modified incisional position. The inferior oblique was not cut or released in any of these cases. There were no observed cases of medial canthal webbing, injury to orbital structures, telecanthus, optic neuropathy, or iatrogenically induced diplopia related to the technique. By definition, the authors' follow-up time is limited to less than 2 years in each case; however, all complications, which the authors have considered for this report, would have been readily observable in this postoperative period

  12. Chondroitin sulphate glycosaminoglycans contribute to widespread inferior biomechanics in tendon after focal injury.

    Science.gov (United States)

    Choi, Rachel K; Smith, Margaret M; Martin, Joshua H; Clarke, Jillian L; Dart, Andrew J; Little, Christopher B; Clarke, Elizabeth C

    2016-09-06

    Both mechanical and structural properties of tendon change after injury however the causal relationship between these properties is presently unclear. This study aimed to determine the extent of biomechanical change in post-injury tendon pathology and whether the sulphated glycosaminoglycans (glycosaminoglycans) present are a causal factor in these changes. Equine superficial digital flexor tendons (SDF tendons) were surgically-injured in vivo (n=6 injured, n=6 control). Six weeks later they were harvested and regionally dissected into twelve regions around the lesion (equal medial/lateral, proximal/distal). Glycosaminoglycans were removed by enzymatic (chondroitinase) treatment. Elastic modulus (modulus) and ultimate tensile strength (UTS) were measured under uniaxial tension to failure, and tendon glycosaminoglycan content was measured by spectrophotometry. Compared to healthy tendons, pathology induced by the injury decreased modulus (-38%; 95%CI -49% to -28%; Ptendon. Chondroitinase-mediated glycosaminoglycan removal (50%; 95%CI 21-79%; Ptendons caused a significant increase in modulus (5.6MPa/µg removed; 95%CI 0.31-11; P=0.038) and UTS (1.0MPa per µg removed; 95%CI 0.043-2; P=0.041). These results demonstrate that the chondroitin/dermatan sulphate glycosaminoglycans that accumulate in pathological tendon post-injury are partly responsible for the altered biomechanical properties. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Field Evaluation of the System Identification Approach for Tension Estimation of External Tendons

    Directory of Open Access Journals (Sweden)

    Myung-Hyun Noh

    2015-01-01

    Full Text Available Various types of external tendons are considered to verify the applicability of tension estimation method based on the finite element model with system identification technique. The proposed method is applied to estimate the tension of benchmark numerical example, model structure, and field structure. The numerical and experimental results show that the existing methods such as taut string theory and linear regression method show large error in the estimated tension when the condition of external tendon is different with the basic assumption used during the derivation of relationship between tension and natural frequency. However, the proposed method gives reasonable results for all of the considered external tendons in this study. Furthermore, the proposed method can evaluate the accuracy of estimated tension indirectly by comparing the measured and calculated natural frequencies. Therefore, the proposed method can be effectively used for field application of various types of external tendons.

  14. The roentgenographic findings of achilles tendon rupture

    Energy Technology Data Exchange (ETDEWEB)

    Seouk, Kang Hyo; Keun, Rho Yong [Shilla General Hospital, Seoul (Korea, Republic of)

    1999-03-01

    To evaluate the diagnostic value of a lateral view of the ankles in Achilles tendon rupture. We performed a retrospective analysis of the roentgenographic findings of 15 patients with surgically proven Achilles tendon rupture. Four groups of 15 patients(normal, ankle sprain, medial lateral malleolar fracture, and calcaneal fracture) were analysed as reference groups. Plain radiographs were reviewed with regard to Kager's triangle, Arner's sign, Toygar's angle, ill defined radiolucent shadow through the Achilles tendon, sharpness of the anterior margin of Achilles tendon, and meniscoid smooth margin of the posterior skin surface of the ankle. Kager's triangle was deformed and disappeared after rupture of the Achilles tendon in nine patients(60%) with operative verification of the rupture, six patients(40%) had a positive Arner's sign, while none had a diminished Toygars angle. In 13 patients(87%) with a ruptured Achilles tendon, the thickness of this was nonuniform compared with the reference group. The anterior margin of the Achilles tendon became serrated and indistinct in 14 patients(93%) in whom this was ruptured. An abnormal ill defined radiolucent shadow through the Achilles tendon was noted in nine patient(60%), and nonparallelism between the anterior margin of the Achilles tendon and posterior skin surface of the ankle was detected in 11 patients(73%). The posterior skin surface of the ankle had a nodular surface margin in 13 patients(87%). A deformed Kager's triangle and Achilles tendon, and an abnormal ill defined radiolucent shadow through the Achilles tendon in a lateral view of the ankles are important findings for the diagnesis of in diagnosing achilles tendon rupture.

  15. Tendon sheath fibroma in the thigh.

    Science.gov (United States)

    Moretti, Vincent M; Ashana, Adedayo O; de la Cruz, Michael; Lackman, Richard D

    2012-04-01

    Tendon sheath fibromas are rare, benign soft tissue tumors that are predominantly found in the fingers, hands, and wrists of young adult men. This article describes a tendon sheath fibroma that developed in the thigh of a 70-year-old man, the only known tendon sheath fibroma to form in this location. Similar to tendon sheath fibromas that develop elsewhere, our patient's lesion presented as a painless, slow-growing soft tissue nodule. Physical examination revealed a firm, nontender mass with no other associated signs or symptoms. Although the imaging appearance of tendon sheath fibromas varies, our patient's lesion appeared dark on T1- and bright on T2-weighted magnetic resonance imaging. It was well marginated and enhanced with contrast.Histologically, tendon sheath fibromas are composed of dense fibrocollagenous stromas with scattered spindle-shaped fibroblasts and narrow slit-like vascular spaces. Most tendon sheath fibromas can be successfully removed by marginal excision, although 24% of lesions recur. No lesions have metastasized. Our patient's tendon sheath fibroma was removed by marginal excision, and the patient remained disease free 35 months postoperatively. Despite its rarity, tendon sheath fibroma should be included in the differential diagnosis of a thigh mass on physical examination or imaging, especially if it is painless, nontender, benign appearing, and present in men. Copyright 2012, SLACK Incorporated.

  16. Simulation of tendon energy storage in pedaling

    DEFF Research Database (Denmark)

    Rasmussen, John; Damsgaard, Michael; Christensen, Søren Tørholm

    2001-01-01

    system is based on inverse dynamics, where the redundancy problem is solved by a minimum fatigue criterion guaranteeing maximuminter-muscular collaboration. The tendons are assumed to be linearly elastic. It is concluded that tendon elasticity is responsible for metabolic power loss......The role of elastic energy stored in tendons during pedaling is investigated by means of numerical simulation using the AnyBody body modeling system. The loss of metabolic energy due to tendon elasticity is computed and compared to the mechanical work involved in the process. The AnyBody simulation...

  17. Early diagnosis of tendon pathologies with sonoelastography

    Directory of Open Access Journals (Sweden)

    Zeynep ilerisoy Yakut

    2015-04-01

    RESULTS: Achilles tendon thicknesses measured at three segments (proximal, middle ,distal. did not show any statistically significant difference in both painless and symptomatic side. Proximal part of achilles tendon's elasticity did not show any difference in both side (p=0.31. In middle and distal segment , the elasticity was statistically different in symptomatic side than normal side p=0.005 and p=0.001 respectively. CONCLUSION: Sonoelastographic examination of Achilles tendons in patients with FMF suffering from talalgia may be useful for determining early dejenerative changes in tendons either in the absence of B-mode ultrasound findings. [TAF Prev Med Bull 2015; 14(2.000: 75-80

  18. Tendon exhibits complex poroelastic behavior at the nanoscale as revealed by high-frequency AFM-based rheology.

    Science.gov (United States)

    Connizzo, Brianne K; Grodzinsky, Alan J

    2017-03-21

    Tendons transmit load from muscle to bone by utilizing their unique static and viscoelastic tensile properties. These properties are highly dependent on the composition and structure of the tissue matrix, including the collagen I hierarchy, proteoglycans, and water. While the role of matrix constituents in the tensile response has been studied, their role in compression, particularly in matrix pressurization via regulation of fluid flow, is not well understood. Injured or diseased tendons and tendon regions that naturally experience compression are known to have alterations in glycosaminoglycan content, which could modulate fluid flow and ultimately mechanical function. While recent theoretical studies have predicted tendon mechanics using poroelastic theory, no experimental data have directly demonstrated such behavior. In this study, we use high-bandwidth AFM-based rheology to determine the dynamic response of tendons to compressive loading at the nanoscale and to determine the presence of poroelastic behavior. Tendons are found to have significant characteristic dynamic relaxation behavior occurring at both low and high frequencies. Classic poroelastic behavior is observed, although we hypothesize that the full dynamic response is caused by a combination of flow-dependent poroelasticity as well as flow-independent viscoelasticity. Tendons also demonstrate regional dependence in their dynamic response, particularly near the junction of tendon and bone, suggesting that the structural and compositional heterogeneity in tendon may be responsible for regional poroelastic behavior. Overall, these experiments provide the foundation for understanding fluid-flow-dependent poroelastic mechanics of tendon, and the methodology is valuable for assessing changes in tendon matrix compressive behavior at the nanoscale. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Structural and functional modulation of early healing of full-thickness superficial digital flexor tendon rupture in rabbits by repeated subcutaneous administration of exogenous human recombinant basic fibroblast growth factor.

    Science.gov (United States)

    Moshiri, Ali; Oryan, Ahmad

    2011-01-01

    The present study was designed to investigate the effects of basic fibroblast growth factor on the healing of the acute phase of complete superficial digital flexor tendon rupture in rabbits. A total of 40 skeletally mature female white New Zealand rabbits were randomly divided into 2 equal groups of injured treated and injured control. After tenotomy and surgical anastomosis, using a modified Kessler and running pattern, the injured legs were placed in casts for 14 days, and basic fibroblast growth factor was injected subcutaneously over the lesion on days 3, 7, and 10 after injury. The injured control rabbits received a normal saline injection in a similar protocol. The rabbits' weight, tendon diameter, clinical signs, radiographs, and ultrasound scans were evaluated weekly. The rabbits were killed 28 days after injury, and the tendons were evaluated at the macroscopic, histopathologic, and ultrastructural levels and for biomechanical and the percentage of dry weight analysis. Treatment significantly reduced the diameter and increased the echogenicity and dry weight content and enhanced the maturation rate of the tenoblasts, fibrillogenesis, collagen fibril diameter, fibrillar density, tensile strength, and stiffness and stress of the injured tendons. Treatment with basic fibroblast growth factor was effective in restoring the morphologic and biomechanical properties of the injured superficial digital flexor tendon and could be valuable in clinical trial studies. Copyright © 2011 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  20. Differences in tendon properties in elite badminton players with or without patellar tendinopathy.

    Science.gov (United States)

    Couppé, C; Kongsgaard, M; Aagaard, P; Vinther, A; Boesen, M; Kjaer, M; Magnusson, S P

    2013-03-01

    The aim of this study was to examine the structural and mechanical properties of the patellar tendon in elite male badminton players with and without patellar tendinopathy. Seven players with unilateral patellar tendinopathy (PT group) on the lead extremity (used for forward lunge) and nine players with no current or previous patellar tendinopathy (CT group) were included. Magnetic resonance imaging was used to assess distal patellar tendon dimensions. Patellar tendon mechanical properties were assessed using simultaneous tendon force and deformation measurements. Distal tendon cross-sectional area (CSA) normalized for body weight (mm(2) /kg(2/3) ) was lower in the PT group compared with the CT group on both the non-lead extremity (6.1 ± 0.3 vs 7.4 ± 0.2, P < 0.05) and the lead extremity (6.5 ± 0.6 vs 8.4 ± 0.3, P < 0.05). Distal tendon stress was higher in the PT group compared with the CT group for both the non-lead extremity (31 ± 1 vs 27 ± 1 MPa, P < 0.05) and the lead extremity (32 ± 3 vs 21 ± 3 MPa, P < 0.01). Conclusively, the PT group had smaller distal patellar tendon CSA on both the injured (lead extremity) and the uninjured side (non-lead extremity) compared with the CT group. Subsequently, the smaller CSA yielded a greater distal patellar tendon stress in the PT group. Therefore, a small tendon CSA may predispose to the development of tendinopathy. © 2012 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

  1. Thermal Preconditioning May Prevent Tendon Adhesion by Up-Regulating HSP72 in Rats.

    Science.gov (United States)

    Tan, Yang; Wu, Qin-Fen; Wu, Qiang; Tan, Xin-Ti; Chen, Liao-Bin; Wang, Xin

    2017-01-01

    The study aims to determine the effects of thermal preconditioning on tendon adhesion by regulating the expression of heat shock protein 72 (HSP72) in rat models. Sixty male Wistar rats were collected and randomly assigned into the thermal preconditioning and control groups. During the 4th and 8th weeks following surgery, 15 rats were sacrificed in each period respectively, and their tendon adhesion was observed and evaluated. Biomechanical testing was performed to measure the tensile strength and gliding distance of tendons. Hematoxylin-eosin (HE) was used to observe the morphological structure of the tendons. Immunohistochemical staining, quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were used to detect the HSP72, fibroblast growth factor-2 (FGF-2), fibroblast growth factor receptor-1 (FGFR-1), β-catenin, epithelial cell adhesion molecule (EPCAM), Tenomodulin and scleraxis protein expressions. Pearson correlation analysis was applied to analyze the correlation between HSP72 expression and tendon adhesion. At the 4th week after surgery, we found no differences in the tendon adhesion scores or mRNA and protein expressions of HSP72 between the thermal preconditioning and control groups. However, after the 8th week after surgery, the thermal preconditioning group had a lower tendon adhesion score and higher mRNA and protein expressions of HSP72 than the control group. During the same period, we found longer gliding distance and higher expression levels of FGF-2, FGFR-1, β-catenin, Tenomodulin and scleraxis, but lower EPCAM expression in the thermal preconditioning group. Pearson correlation analysis indicated that HSP72 mRNA and protein expression levels were negatively correlated with tendon adhesion. These findings provide evidence that thermal preconditioning may alleviate tendon adhesions via upregulation of HSP72 expression. © 2017 The Author(s). Published by S. Karger AG, Basel.

  2. Lineage tracing of resident tendon progenitor cells during growth and natural healing.

    Directory of Open Access Journals (Sweden)

    Nathaniel A Dyment

    Full Text Available Unlike during embryogenesis, the identity of tissue resident progenitor cells that contribute to postnatal tendon growth and natural healing is poorly characterized. Therefore, we utilized 1 an inducible Cre driven by alpha smooth muscle actin (SMACreERT2, that identifies mesenchymal progenitors, 2 a constitutively active Cre driven by growth and differentiation factor 5 (GDF5Cre, a critical regulator of joint condensation, in combination with 3 an Ai9 Cre reporter to permanently label SMA9 and GDF5-9 populations and their progeny. In growing mice, SMA9+ cells were found in peritendinous structures and scleraxis-positive (ScxGFP+ cells within the tendon midsubstance and myotendinous junction. The progenitors within the tendon midsubstance were transiently labeled as they displayed a 4-fold expansion from day 2 to day 21 but reduced to baseline levels by day 70. SMA9+ cells were not found within tendon entheses or ligaments in the knee, suggesting a different origin. In contrast to the SMA9 population, GDF5-9+ cells extended from the bone through the enthesis and into a portion of the tendon midsubstance. GDF5-9+ cells were also found throughout the length of the ligaments, indicating a significant variation in the progenitors that contribute to tendons and ligaments. Following tendon injury, SMA9+ paratenon cells were the main contributors to the healing response. SMA9+ cells extended over the defect space at 1 week and differentiated into ScxGFP+ cells at 2 weeks, which coincided with increased collagen signal in the paratenon bridge. Thus, SMA9-labeled cells represent a unique progenitor source that contributes to the tendon midsubstance, paratenon, and myotendinous junction during growth and natural healing, while GDF5 progenitors contribute to tendon enthesis and ligament development. Understanding the mechanisms that regulate the expansion and differentiation of these progenitors may prove crucial to improving future repair strategies.

  3. Comparison of the Achilles tendon moment arms determined using the tendon excursion and three?dimensional methods

    OpenAIRE

    Hashizume, Satoru; Fukutani, Atsuki; Kusumoto, Kazuki; Kurihara, Toshiyuki; Yanagiya, Toshio

    2016-01-01

    Abstract The moment arm of muscle?tendon force is a key parameter for calculating muscle and tendon properties. The tendon excursion method was used for determining the Achilles tendon moment arm (ATMA). However, the accuracy of this method remains unclear. This study aimed to investigate the magnitude of error introduced in determining the ATMA using the tendon excursion method by comparing it with the reference three?dimensional (3D) method. The tendon excursion method determined the ATMA a...

  4. Tendon mineralization is accelerated bilaterally and creep of contralateral tendons is increased after unilateral needle injury of murine achilles tendons.

    Science.gov (United States)

    O'Brien, Etienne John Ogilvy; Shrive, Nigel G; Rosvold, Joshua M; Thornton, Gail M; Frank, Cyril B; Hart, David A

    2013-10-01

    Heterotopic mineralization may result in tendon weakness, but effects on other biomechanical responses have not been reported. We used a needle injury, which accelerates spontaneous mineralization of murine Achilles tendons, to test two hypotheses: that injured tendons would demonstrate altered biomechanical responses; and that unilateral injury would accelerate mineralization bilaterally. Mice underwent left hind (LH) injury (I; n = 11) and were euthanized after 20 weeks along with non-injured controls (C; n = 9). All hind limbs were examined by micro computed tomography followed by biomechanical testing (I = 7 and C = 6). No differences were found in the biomechanical responses of injured tendons compared with controls. However, the right hind (RH) tendons contralateral to the LH injury exhibited greater static creep strain and total creep strain compared with those LH tendons (p ≤ 0.045) and RH tendons from controls (p ≤ 0.043). RH limb lesions of injured mice were three times larger compared with controls (p = 0.030). Therefore, despite extensive mineralization, changes to the responses we measured were limited or absent 20 weeks postinjury. These results also suggest that bilateral occurrence should be considered where tendon mineralization is identified clinically. This experimental system may be useful to study the mechanisms of bilateral new bone formation in tendinopathy and other conditions. Copyright © 2013 Orthopaedic Research Society.

  5. Detection of partial-thickness tears in ligaments and tendons by Stokes-polarimetry imaging

    Science.gov (United States)

    Kim, Jihoon; John, Raheel; Walsh, Joseph T.

    2008-02-01

    A Stokes polarimetry imaging (SPI) system utilizes an algorithm developed to construct degree of polarization (DoP) image maps from linearly polarized light illumination. Partial-thickness tears of turkey tendons were imaged by the SPI system in order to examine the feasibility of the system to detect partial-thickness rotator cuff tear or general tendon pathology. The rotating incident polarization angle (IPA) for the linearly polarized light provides a way to analyze different tissue types which may be sensitive to IPA variations. Degree of linear polarization (DoLP) images revealed collagen fiber structure, related to partial-thickness tears, better than standard intensity images. DoLP images also revealed structural changes in tears that are related to the tendon load. DoLP images with red-wavelength-filtered incident light may show tears and related organization of collagen fiber structure at a greater depth from the tendon surface. Degree of circular polarization (DoCP) images exhibited well the horizontal fiber orientation that is not parallel to the vertically aligned collagen fibers of the tendon. The SPI system's DOLP images reveal alterations in tendons and ligaments, which have a tissue matrix consisting largely of collagen, better than intensity images. All polarized images showed modulated intensity as the IPA was varied. The optimal detection of the partial-thickness tendon tears at a certain IPA was observed. The SPI system with varying IPA and spectral information can improve the detection of partial-thickness rotator cuff tears by higher visibility of fiber orientations and thereby improve diagnosis and treatment of tendon related injuries.

  6. Masticatory muscle tendon-aponeurosis hyperplasia exhibits heterotopic calcification in tendons.

    Science.gov (United States)

    Sato, T; Hori, N; Nakamoto, N; Akita, M; Yoda, T

    2014-05-01

    Masticatory muscle tendon-aponeurosis hyperplasia is a new disease entity associated with limited mouth opening. In this study, we analyzed the microstructural characteristics of muscles and tendons in masticatory muscle tendon-aponeurosis hyperplasia by electron microscopy and energy-dispersive X-ray analysis to determine the elemental composition. Histological analysis was performed to detect the calcification. Transmission electron microscopy and scanning electron microscopy were conducted to clarify the microstructural characteristics of muscles and tendons. Energy-dispersive X-ray microanalysis was performed to identify the distribution of elements. Mineralized nodules were observed in tendon tissues of masticatory muscle tendon-aponeurosis hyperplasia as compared with facial deformity. Electron microscopy revealed that the muscle and tendon tissues in masticatory muscle tendon-aponeurosis hyperplasia showed degenerative changes and distinctive histological findings as compared with tissues in facial deformity. We found that Ca, P, and Si were detected only in masticatory muscle tendon-aponeurosis hyperplasia. We demonstrated that masticatory muscle tendon-aponeurosis hyperplasia exhibits heterotopic calcification in tendon tissues. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Single-stage reconstruction of flexor tendons with vascularized tendon transfers.

    Science.gov (United States)

    Cavadas, P C; Pérez-García, A; Thione, A; Lorca-García, C

    2015-03-01

    The reconstruction of finger flexor tendons with vascularized flexor digitorum superficialis (FDS) tendon grafts (flaps) based on the ulnar vessels as a single stage is not a popular technique. We reviewed 40 flexor tendon reconstructions (four flexor pollicis longus and 36 finger flexors) with vascularized FDS tendon grafts in 38 consecutive patients. The donor tendons were transferred based on the ulnar vessels as a single-stage procedure (37 pedicled flaps, three free flaps). Four patients required composite tendon and skin island transfer. Minimum follow-up was 12 months, and functional results were evaluated using a total active range of motion score. Multiple linear regression analysis was performed to evaluate the factors that could be associated with the postoperative total active range of motion. The average postoperative total active range of motion (excluding the thumbs) was 178.05° (SD 50°). The total active range of motion was significantly lower for patients who were reconstructed with free flaps and for those who required composite tendon and skin island flap. Age, right or left hand, donor/motor tendon and pulley reconstruction had no linear effect on total active range of motion. Overall results were comparable with a published series on staged tendon grafting but with a lower complication rate. Vascularized pedicled tendon grafts/flaps are useful in the reconstruction of defects of finger flexor tendons in a single stage, although its role in the reconstructive armamentarium remains to be clearly established. © The Author(s) 2014.

  8. Flexor tendon physiology: tendon nutrition and cellular activity in injury and repair.

    Science.gov (United States)

    Gelberman, R H

    1985-01-01

    Scientific studies of the past 20 years have done much to redefine the mechanisms by which flexor tendons heal. Several points have become increasingly clear: Flexor tendons are nourished to a greater extent by synovial fluid diffusion than vascular perfusion. Tendon cells are capable of proliferating, producing collagen, and reconstructing their own gliding surface in the absence of adhesion ingrowth. The key to a successful outcome after flexor tendon repair appears to be an early restoration of tendon continuity, reconstruction of the sheath, if possible, and early passive mobilization. This complex stimulates the tendon's intrinsic repair potential, which is contained within the cells of the tendon itself but appears to be expressed only under ideal experimental and clinical situations.

  9. From Tendon Injury to Collagen-based Tendon Regeneration: Overview and Recent Advances.

    Science.gov (United States)

    Rieu, Clement; Picaut, Lise; Mosser, Gervaise; Trichet, Lea

    2017-01-01

    Tendon injury is a clinical, societal and economical issue. Moreover, tendon repair represents an important clinical challenge, partly due to the mechanical constraints that occur at the junctions with muscle and bone. Several strategies have been developed for tendon repair. In this review, we first assess the importance of tendon injuries from different sites and their causes. After a short overview of tendon three-dimensional organization, the complexity of the perfect repair quest is presented ranging from current clinical procedures to new engineering scaffolds. We then sum up tendon engineering requirements and focus on new collagen-based scaffolds, which raise promising prospects to mimic and repair tendon. In particular, we survey quantitatively a large panel of techniques to produce these scaffolds, detailing their principle and recent improvements. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  10. Firm anchoring between a calcium phosphate-hybridized tendon and bone for anterior cruciate ligament reconstruction in a goat model

    Energy Technology Data Exchange (ETDEWEB)

    Mutsuzaki, Hirotaka [Department of Orthopaedic Surgery, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan); Sakane, Masataka; Ochiai, Naoyuki [Department of Orthopaedic Surgery, Institute of Clinical Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575 (Japan); Hattori, Shinya; Kobayashi, Hisatoshi, E-mail: sakane-m@md.tsukuba.ac.j [Biomaterial Center, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

    2009-08-15

    Using an alternative soaking process improved the tendon-bone attachment for a calcium phosphate (CaP)-hybridized tendon graft. We characterized the deposited CaP on and in tendons and analyzed the histology and mechanical properties of the tendon-bone interface in anterior cruciate ligament (ACL) reconstruction in goats. The tendon grafts to be implanted were soaked ten times alternately in a Ca-containing solution and a PO{sub 4}-containing solution for 30 s each. Needlelike CaP nanocrystals including low-crystalline apatite were deposited on and between collagen fibrils from the surface to a depth of 200{mu}m inside the tendon. The structure resembles the extracellular matrix of bone. In animal experiments, the CaP-hybridized tendon directly bonded with newly formed bone at 6 weeks (n = 3), while fibrous bonding was observed in the control (n = 3). The ultimate failure load was not statistically different between the CaP (n = 7) and control (n = 7). However, in the failure mode, all the tendon-bone interfaces were intact in the CaP group, while three of seven specimens were pulled out from bone tunnels in the control. The result suggested that the strength of the tendon-bone interface in the CaP group is superior to that in the control group. Clinically, firm tendon-bone anchoring may lead to good results without the knee instability associated with the loosening of the bone-tendon junction in ACL reconstruction.

  11. Multilayered polycaprolactone/gelatin fiber-hydrogel composite for tendon tissue engineering.

    Science.gov (United States)

    Yang, Guang; Lin, Hang; Rothrauff, Benjamin B; Yu, Shuting; Tuan, Rocky S

    2016-04-15

    Regeneration of injured tendon and ligament (T&L) remains a clinical challenge due to their poor intrinsic healing capacity. Tissue engineering provides a promising alternative treatment approach to facilitate T&L healing and regeneration. Successful tendon tissue engineering requires the use of three-dimensional (3D) biomimetic scaffolds that possess the physical and biochemical features of native tendon tissue. We report here the development and characterization of a novel composite scaffold fabricated by co-electrospinning of poly-ε-caprolactone (PCL) and methacrylated gelatin (mGLT). We found that photocrosslinking retained mGLT, resulted in a uniform distribution of mGLT throughout the depth of scaffold and also preserved scaffold mechanical strength. Moreover, photocrosslinking was able to integrate stacked scaffold sheets to form multilayered constructs that mimic the structure of native tendon tissues. Importantly, cells impregnated into the constructs remained responsive to topographical cues and exogenous tenogenic factors, such as TGF-β3. The excellent biocompatibility and highly integrated structure of the scaffold developed in this study will allow the creation of a more advanced tendon graft that possesses the architecture and cell phenotype of native tendon tissues. The clinical challenges in tendon repair have spurred the development of tendon tissue engineering approaches to create functional tissue replacements. In this study, we have developed a novel composite scaffold as a tendon graft consisting of aligned poly-ε-caprolactone (PCL) microfibers and methacrylated gelatin (mGLT). Cell seeding and photocrosslinking between scaffold layers can be performed simultaneously to create cell impregnated multilayered constructs. This cell-scaffold construct combines the advantages of PCL nanofibrous scaffolds and photocrosslinked gelatin hydrogels to mimic the structure, mechanical anisotropy, and cell phenotype of native tendon tissue. The scaffold

  12. The pathology of flexor tendon repair.

    Science.gov (United States)

    Matthews, P

    1979-10-01

    This paper discusses the problems of failure after tendon repair. For a long time the subject has been dominated by the problem of adhesion formation. Recent work has shown that this is not inevitable, and consideration of other factors, particularly the nutrition of tendon tissue is leading to the possibilities of other methods of treatment.

  13. Flexor tendon specimens in organ cultures.

    Science.gov (United States)

    Rank, F; Eiken, O; Bergenholtz, A; Lundborg, G; Erkel, L J

    1980-01-01

    The healing process of sectioned and subsequently sutured rabbit tendon segments was studied over a period of 3 weeks, using an organ culture technique. In one series, the tendon specimens were exposed to a chemically defined culture medium for nutrition. In two control series, the specimens were kept in the synovial cavity of the knee joint for varying periods of time, before being transferred to the culture medium. The tendons remained viable in the medium. The superficial tendon cells demonstrated the morphological characteristics of fibroblasts, but cellular fibroplasia could not be detected. The two control series subjected to synovia prior to transfer into the culture medium showed superficial repair similar to the findings in previous studies on healing capacity of tendon nourished by synovia. The investigation supports the hypothesis that superficial tendon cells are fibroblasts with a potential for repair and that synovia is an efficient nutrient medium. Thus, the beneficial effects on repair exercised by the tendon sheath function should be utilized in flexor tendon surgery.

  14. [Spontaneous achilles tendon rupture in granulomatous vasculitis].

    Science.gov (United States)

    Benthien, Jan Philipp; Delling, G; Rüther, W

    2003-08-01

    A 66-year old patient sustained a non-traumatic rupture of her left achilles tendon. She suffered from Sjögren's syndrome which occurred in conjunction with a systemic vasculitis, and recurrent episcleritis. The combination of Sjögren's syndrome and systemic vasculitis is well known. Subsequently, she was treated with high-dose systemic steroids over a period of 2 years. In order to reduce the amount of steroids due to preexisting severe osteoporosis and thoracic vertebral fractures, her medication was changed to cyclophosphamide shortly before her injury. Intraoperatively, a granuloma was discovered at the site of the rupture. This granuloma had infiltrated most of the achilles tendon at this site and virtually replaced viable tendon tissue. Originally, the rupture was supposedly due to the high dose steroids. This theory had to be revised according to the intraoperative findings. Following excision of the granuloma and operative treatment of the achilles tendon rupture, the continuity of the tendon could be completely restored. A MRI scan 3 months after the procedure demonstrated a completely healed Achilles tendon. Spontaneous achilles tendon rupture due to a granuloma in patients with vasculitis seems to be a rare event. However, tendon ruptures in combination with systemic lupus erythematodes have been described. Mostly, these events are attributed to long term application of steroids. Spontaneous rupture in combination with high dose treatment of steroids seems to be an underestimated problem.

  15. Recent advances in flexor tendon repair

    NARCIS (Netherlands)

    J.C.H.M. van der Meulen (Jacques)

    1971-01-01

    markdownabstractThe prognosis for restoration of good function after the treatment of a tendon lesion in 'no-man's land' is influenced by a number of factors which may be summarized as follows: - The nature of the injury. - The amplitude of the tendon excursion. - The motility of the

  16. Ultrasonographic assessment of the equine palmar tendons.

    Science.gov (United States)

    Padaliya, N R; Ranpariya, J J; Kumar, Dharmendra; Javia, C B; Barvalia, D R

    2015-02-01

    The present study was conducted to evaluate the equine palmar tendon by ultrasonography (USG) in standing the position. USG of palmar tendons was performed in 40 adult horses using linear transducer having frequency of 10-18 MHz (e-soate, My Lab FIVE) and L52 linear array transducer (Titan, SonoSite) with frequencies ranging from 8 to 10 MHz. Palmar tendon was divided into 7 levels from distal to accessory carpal bone up to ergot in transverse scanning and 3 levels in longitudinal scanning. The USG evaluation was very useful for diagnosis of affections of the conditions such as chronic bowed tendon, suspensory ligament desmitis, carpal sheath tenosynovitis and digital sheath effusions. The mean cross-sectional area (cm(2)) of affected tendons was significantly increased in affected than normal tendons. The echogenicity was also found reduced in affected tendons and ligaments along with disorganization of fiber alignment depending on the severity of lesion and injury. USG proved ideal diagnostic tool for diagnosis and post-treatment healing assessment of tendon injuries in horses.

  17. MANAGEMENT OF OPEN ACHILLES TENDON INJURY: PRIMARY ...

    African Journals Online (AJOL)

    is attributable to increase in both competitive and recreational sports. In most of the literature written on Achilles tendon injuries there were rarely any information about open Achilles tendon lacerations. In ... Methods: This was a prospective study that took place at the Plastic Surgery Unit of Irrua Specialist. Teaching Hospital ...

  18. Instructive materials for tendon and ligament augmentation

    NARCIS (Netherlands)

    Ribeiro Pereira Simões Crispim, João Francisco

    2016-01-01

    Tendons and ligaments (T/L) are the connective tissue that connect muscles to bone and bone to bone, respectively. The main function of tendons is to translate muscle contractions into join motion and consequently generate movement. Ligaments function to stabilize joints and guide them during their

  19. Bilateral synchronous rupture of the quadriceps tendon.

    LENUS (Irish Health Repository)

    Ellanti, P

    2012-09-01

    Bilateral simultaneous rupture of the quadriceps tendon is a rare entity. They are often associated with degenerative changes of the tendons and predisposing conditions such as diabetes or excessive steroid use. They most commonly tend to occur in patients of 40 years of age or older.

  20. Tendon xanthomas : Not always familial hypercholesterolemia

    NARCIS (Netherlands)

    Koopal, Charlotte; Visseren, Frank L J; Marais, A David; Westerink, Jan; Spiering, Wilko

    2016-01-01

    Tendon xanthoma are most commonly associated with Familial Hypercholesterolemia, but the differential diagnosis includes sitosterolemia and cerebrotendinous xanthomatosis (CTX). The case presented here is of a 48-year old male with large tendon xanthomas attributable to CTX. CTX is a rare, recessive

  1. Rupture of Achilles Tendon : Usefulness of Ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Nam Hyeon; Ki, Won Woo; Yoon, Kwon Ha; Kim, Song Mun; Shin, Myeong Jin [Ulsan Medical College, Ulsan (Korea, Republic of); Kwon, Soon Tae [Chungnam University College of Medicine, Daejeon (Korea, Republic of)

    1996-06-15

    To differentiate a complete rupture of Achilles tendon from an incomplete one which is important because its treatment is quite different. And it is necessary to know the exact site of the rupture preoperatively. Fifteen cases of fourteen patients which were diagnosed as Achilles tendon rupture by ultrasonography and surgery were reviewed. We compared sonographic rupture site with surgical findings. Ultrasonographic criteria for differentiation of complete and incomplete rupture was defined as follows : the discreteness, which means the proximal intervening hypoechogenicity to the interface echogenicity of distal margin of ruptured tendon : the slant sign, which represents the interface of ruptured distal margin which was seen over the 3/4 of the thickness of the tendon without intervening low echogeneicity : the invagination sign, which means the echogenic invagination from Kager triangle into posterior aspect of Achilles tendon over the half thickness of the tendon. The sites of complete tendon rupture were exactly corresponded to surgical finding in four cases of ten complete ruptures. And the discrepancy between sonographic and surgical findings in the site of complete rupture was 1.2 {+-} 0.4 cm in six cases. Three of ten complete ruptures showed the discreteness sign, all of ten showed the slant sign and two of ten showed the invagination sign. It is helpful to differentiate a complete from incomplete rupture of the Achilles tendon and to localize the site of the complete rupture with the ultrasonographic evaluation

  2. GH receptor blocker administration and muscle-tendon collagen synthesis in humans

    DEFF Research Database (Denmark)

    Nielsen, Rie H; Doessing, Simon; Goto, K.

    2011-01-01

    Collagen is the predominant structural protein in tendons and ligaments, and can be controlled by hormonal changes. In animals, injections of insulin-like growth factor I (IGF-I) has been shown to increase collagen synthesis in tendons and ligaments and to improve structural tissue healing......, but the effect of local IGF-I administration on tendon collagen synthesis in human has not been studied. The purpose of this study was to study whether local injections of IGF-I would have a stimulating effect on tendon collagen synthesis. Twelve healthy nonsmoking men [age 62 ± 1 years (mean ± SEM), BMI 27 ± 1......] participated. Two injections of either human recombinant IGF-I (0.1 mL Increlex©) or saline (control) into each patellar tendon were performed 24-h apart, respectively. Tendon collagen fractional synthesis rate (FSR) was measured by stable isotope technique in the hours after the second injection...

  3. Effects of flunixin meglumine on experimental tendon wound healing: A histopathological and mechanical study in rabbits

    Science.gov (United States)

    Behfar, Mehdi; Hobbenaghi, Rahim; Sarrafzadeh-Rezaei, Farshid

    2013-01-01

    Tendons are frequently targets of injury in sports and work. Whether nonsteroidal anti-inflammatory drugs (NSAIDs) have beneficial effects on tendon healing is still a matter of debate. This study was conducted to evaluate effects of flunixin meglumine (FM) on tendon healing after experimentally induced acute trauma. Twenty eight adult male New Zealand White rabbits were subjected to complete transection of deep digital flexor tendons followed by suture placement. Treatment group received intramuscular injection of FM for three days, and controls received placebo. Subsequently, cast immobilization was continued for two weeks. Animals were sacrificed four weeks after surgery and tissue samples were taken. The histological evaluations revealed improved structural characteristics of neotendon formation including fibrillar linearity, fibrillar continuity and neovascularization in treatment group compared to those of controls (p 0.05). Mechanical evaluation revealed significant increase in load-related material properties including ultimate load, yield load, energy absorption and ultimate stress in treatment group compared to those of control group (p 0.05). The present study showed that intramuscular injection of FM resulted in improved structural and mechanical properties of tendon repairs and it could be an effective treatment for acute tendon injuries like severance and laceration. PMID:25568677

  4. Effects of flunixin meglumine on experimental tendon wound healing: A histopathological and mechanical study in rabbits

    Directory of Open Access Journals (Sweden)

    Mehdi Behfar

    2014-12-01

    Full Text Available Tendons are frequently targets of injury in sports and work. Whether nonsteroidal anti-inflammatory drugs (NSAIDs have beneficial effects on tendon healing is still a matter of debate. This study was conducted to evaluate effects of flunixin meglumine (FM on tendon healing after experimentally induced acute trauma. Twenty eight adult male New Zealand White rabbits were subjected to complete transection of deep digital flexor tendons followed by suture placement. Treatment group received intramuscular injection of FM for three days, and controls received placebo. Subsequently, cast immobilization was continued for two weeks. Animals were sacrificed four weeks after surgery and tissue samples were taken. The histological evaluations revealed improved structural characteristics of neotendon formation including fibrillar linearity, fibrillar continuity and neovascularization in treatment group compared to those of controls (p 0.05. Mechanical evaluation revealed significant increase in load-related material properties including ultimate load, yield load, energy absorption and ultimate stress in treatment group compared to those of control group (p 0.05. The present study showed that intramuscular injection of FM resulted in improved structural and mechanical properties of tendon repairs and it could be an effective treatment for acute tendon injuries like severance and laceration.

  5. Tendon Vasculature in Health and Disease

    Science.gov (United States)

    Tempfer, Herbert; Traweger, Andreas

    2015-01-01

    Tendons represent a bradytrophic tissue which is poorly vascularized and, compared to bone or skin, heal poorly. Usually, a vascularized connective scar tissue with inferior functional properties forms at the injury site. Whether the increased vascularization is the root cause of tissue impairments such as loss of collagen fiber orientation, ectopic formation of bone, fat or cartilage, or is a consequence of these pathological changes remains unclear. This review provides an overview of the role of tendon vasculature in healthy and chronically diseased tendon tissue as well as its relevance for tendon repair. Further, the nature and the role of perivascular tendon stem/progenitor cells residing in the vascular niche will be discussed and compared to multipotent stromal cells in other tissues. PMID:26635616

  6. Simultaneous bilateral patellar tendon rupture without

    Directory of Open Access Journals (Sweden)

    LU Hua-ding

    2012-04-01

    Full Text Available 【Abstract】There is a dearth of case reports de-scribing simultaneous bilateral patellar tendon ruptures in the medical literature. These ruptures are often associated with systemic disorders such as lupus erythematosus or chronic steroid use. The author describes a case of a 24-year-old man who sustained traumatic bilateral patellar ten-don ruptures without any history of systemic disease or steroidal medication. We repaired and reattached the rup-tured tendons to the patella and augmented our procedure with allogeneic tendon followed by wire loop reinforcement. One year after operation, the patient regained a satisfactory range of motion of both knees with good quadriceps strength and no extensor lag. The recurrent microtrauma from a history of intense sports activity and a high body mass index may have played an important role in this trauma event. Key words: Patella; Patellar ligament; Rupture; Ten-don injuries; Knee

  7. [Applied anatomy of the distal "vinculum tendinis" in the fetlock tendon sheath of the hindlimb in cattle].

    Science.gov (United States)

    Waibl, H; Herrmann, J; Rehage, J; Lorenzi, P; Constantinescu, G

    2001-06-01

    A relatively thick (diameter approximately 2 mm), ropelike (length ca. 20 mm) and elastic "Vinculum tendinis" connects--within the fetlock tendon sheath--the dorsal side of the deep digital flexor tendon with the dorsal part of the Manica flexoria (the communicating band of the Musculus interosseous medius to the superficial digital flexor tendon). The extensive fetlock tendon sheath can be involved in diseases such as aseptic and septic inflammations. Spreading of these inflammations makes in some of these cases the partial resection of the tendon of the deep digital flexor muscle and the cutting of these Vincula necessary. The results of this contribution, collected from 60 hindlimbs of adult bovines show variations in number, length, diameter and extent and the inner structure with blood vessels and nerves.

  8. Achillodynia. Radiological imaging of acute and chronic overuse injuries of the Achilles tendon; Achillodynie. Radiologische Bildgebung bei akuten und chronischen Ueberlastungsschaeden der Achillessehne

    Energy Technology Data Exchange (ETDEWEB)

    Syha, R.; Springer, F.; Grosse, U. [Tuebingen Univ. (Germany). Diagnostic and Interventional Radiology; Tuebingen Univ. (Germany). Section on Experimental Radiology; Ketelsen, D.; Kramer, U.; Horger, M. [Tuebingen Univ. (Germany). Diagnostic and Interventional Radiology; Ipach, I. [University Hospital Tuebingen (Germany). Orthopaedic Surgery; Schick, F. [Tuebingen Univ. (Germany). Section on Experimental Radiology

    2013-11-15

    In the past decades the incidence of acute and chronic disorders of the Achilles tendon associated with sport-induced overuse has steadily increased. Besides acute complete or partial ruptures, achillodynia (Achilles tendon pain syndrome), which is often associated with tendon degeneration, represents the most challenging entity regarding clinical diagnostics and therapy. Therefore, the use of imaging techniques to differentiate tendon disorders and even characterize structure alterations is of growing interest. This review article discusses the potential of different imaging techniques with respect to the diagnosis of acute and chronic tendon disorders. In this context, the most commonly used imaging techniques are magnetic resonance imaging (MRI), B-mode ultrasound, and color-coded Doppler ultrasound (US). These modalities allow the detection of acute tendon ruptures and advanced chronic tendon disorders. However, the main disadvantages are still the low capabilities in the detection of early-stage degeneration and difficulties in the assessment of treatment responses during follow-up examinations. Furthermore, differentiation between chronic partial ruptures and degeneration remains challenging. The automatic contour detection and texture analysis may allow a more objective and quantitative interpretation, which might be helpful in the monitoring of tendon diseases during follow-up examinations. Other techniques to quantify tendon-specific MR properties, e.g. based on ultrashort echo time (UTE) sequences, also seem to have great potential with respect to the precise detection of degenerative tendon disorders and their differentiation at a very early stage. (orig.)

  9. Thompson Test in Achilles Tendon Rupture

    Directory of Open Access Journals (Sweden)

    Spencer Albertson

    2016-07-01

    Full Text Available HPI: A 26-year old male presented to the emergency department after experiencing the acute onset of left ankle pain while playing basketball. Upon jumping, he felt a “pop” in his left posterior ankle, followed by pain and difficulty ambulating. His exam was notable for a defect at the left Achilles tendon on palpation. The practitioner performed a Thompson test, which was positive (abnormal on the left. Significant Findings: The left Achilles tendon had a defect on palpation, while the right Achilles tendon was intact. When squeezing the right (unaffected calf, the ankle spontaneously plantar flexed, indicating a negative (normal Thompson test. Upon squeeze of the left (affected calf, the ankle did not plantar flex, signifying a positive (abnormal Thompson test. The diagnosis of left Achilles tendon rupture was confirmed intraoperatively one week later. Discussion: The Achilles tendon (also: calcaneal tendon or heel cord is derived from the medial and lateral heads of the gastrocnemius muscle, as well as the soleus muscle. Rupture of the Achilles tendon most commonly occurs in the distal tendon, approximately 2-6 cm from its attachment to the calcaneal tuberosity, in an area of hypovascularity known as the “watershed” or “critical” zone.1-3 The Thompson test (also: Simmonds-Thompson test, described by Simmonds in 1957 and Thompson in 1962, is done while the patient is in the prone position, with feet hanging over the end of a table/gurney, or with the patient kneeling on a stool or chair.4-5 Squeezing the calf of an unaffected limb will cause the ankle to plantar flex, but squeezing the calf of a limb with an Achilles tendon rupture will cause no motion. The sensitivity of the Thompson’s test for the diagnosis of a complete Achilles tendon rupture is 96-100% and the specificity is 93-100%, but data is limited.6-8

  10. Arthroscopic suture retrievers and shuttles: a biomechanical investigation of the force required for tendon penetration and defect size.

    Science.gov (United States)

    Lenz, Christopher G; Wieser, Karl; Lajtai, Georg; Meyer, Dominik C

    2015-11-17

    To compare instruments designed for arthroscopic suture handling during arthroscopic rotator cuff repair, to assess the force needed to penetrate the tendon, and to evaluate the residual defect size. Twenty-one instruments were each tested ten times on thawed sheep infraspinatus tendons. The force needed to pierce the tendon with each instrument was measured using a custom setup. Bone wax plates were used to make the perforation marks visible and to quantify the lesions each instrument created. The force to pierce a tendon had a range of 5.6-18.5 N/mm. Within the group of suture retrievers, the angled instruments required in average 85 % higher forces than straight instruments. The lesion area had a range of 2-7 mm(2). Suture retrievers produced significantly larger lesion sizes compared with suture shuttles. For the identical task of passing a suture through a tendon, differences exist regarding the ease of tendon penetration and potential damage to the tendon for different tools. The design, function, and resulting lesion size may be relevant and important for surgical handling and to avoid excess structural damage to the tendon. These results suggest that choosing the most appropriate tools for arthroscopic suture stitching influences the ease of handling and final integrity of the tissue.

  11. [Clinical application of peroneal muscles tendon transposition in repair of Achilles tendon rupture].

    Science.gov (United States)

    Jin, Rihao; Jin, Yu; Fang, Xiulin

    2006-07-01

    To discuss applied anatomy, biomechanics and surgical procedures of long peroneal muscles tendon transposition in repair of occlusive achilles tendon rupture. The blood supply and the morphology of long peroneal muscles tendon were observed in the lower extremity of 50 sides adult specimens and the mechanical tests which stretch load on the tendon were carried out. The methods were designed on the basis of the anatomical characteristics and morphology. Ten patients suffering occlusive Achilles tendon rupture were treated by using long peroneal muscles tendon transposition from March 2001 to July 2004. Among 10 patients, there were 7 males and 3 females, aging 32 to 54 years including 6 cases of jump injury, 2 cases of bruise, 1 case of step vacancy and 1 case of spontaneity injury. The interval between injury and surgery was 6 hours to 7 days in 7 fresh rupture and 21 days to 3 months in 3 old rupture. All cases belonged to occlusive Achilles tendon rupture (8 cases of complete rupture and 2 cases of incomplete rupture). The origin of long peroneal muscles was proximal tibia and fibular head, the end of them was base of first metatarsal bones and medial cuboid. The length of tendon was 13.5 +/- 2.5 cm. The width of origin tendon was 0.9 +/- 0.2 cm and the thickness was 0.3 +/- 0.1 cm; the width on apex of lateral malleolus was 0.7 +/- 0.1 cm and the thickness was 0.4 +/- 0.1 cm, the width on head of cuboid was 0.7 +/- 0.1 cm and the thickness was 0.3 +/- 0.1 cm. The long peroneal muscles tendon had abundant blood supply. The results of mechanical test showed that the biggest load was 2,292.4 +/- 617.3 N on tendon calcaneus, 1,020.4 +/- 175.4 N on long peroneal muscles tendon, 752.0 +/- 165.4 N on peroneus brevis tendon and 938.2 +/- 216.7 N on tibialis posterior tendon. Ten cases of occlusive Achilles tendon rupture achieved healing by first intention and were followed up 18-24 months. No Achilles tendon re-rupture, necrosis of skin or other complications occurred

  12. Studies in flexor tendon reconstruction: biomolecular modulation of tendon repair and tissue engineering.

    Science.gov (United States)

    Chang, James

    2012-03-01

    The Andrew J. Weiland Medal is presented each year by the American Society for Surgery of the Hand and the American Foundation for Surgery of the Hand for a body of work related to hand surgery research. This essay, awarded the Weiland Medal in 2011, focuses on the clinical need for flexor tendon reconstruction and on investigations into flexor tendon biology. Reconstruction of the upper extremity is limited by 2 major problems after injury or degeneration of the flexor tendons. First, adhesions formed after flexor tendon repair can cause decreased postoperative range of motion and hand function. Second, tendon losses can result from trauma and degenerative diseases, necessitating additional tendon graft material. Tendon adhesions are even more prevalent after tendon grafting; therefore these 2 problems are interrelated and lead to considerable disability. The total costs in terms of disability and inability to return to work are enormous. In this essay, published work from the past 12 years in our basic science laboratory is summarized and presented with the common theme of using molecular techniques to understand the cellular process of flexor tendon wound healing and to create substances and materials to improve tendon repair and regeneration. These are efforts to address 2 interrelated and clinically relevant problems that all hand surgeons face in their practice. Copyright © 2012 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  13. Elastographic characteristics of the metacarpal tendons in horses without clinical evidence of tendon injury.

    Science.gov (United States)

    Lustgarten, Meghann; Redding, W Rich; Labens, Raphael; Morgan, Michel; Davis, Weston; Seiler, Gabriela S

    2014-01-01

    Tendon and ligament injuries are common causes of impaired performance in equine athletes. Gray-scale ultrasonography is the current standard method for diagnosing and monitoring these injuries, however this modality only provides morphologic information. Elastography is an ultrasound technique that allows detection and measurement of tissue strain, and may provide valuable mechanical information about equine tendon and ligament injuries. The purpose of this study was to determine the feasibility, reproducibility, and repeatability of elastography; and to describe elastographic characteristics of metacarpal tendons in sound horses. Nineteen legs for 17 clinically sound horses without evidence of musculoskeletal pathology were included. Elastographic images of the superficial and deep digital flexor tendons and the branches of the suspensory ligament (tendon of the interosseous muscle) were described quantitatively and qualitatively. There was no statistically significant difference between operators (P = 0.86) nor within operators (P = 0.93). For qualitative assessments, reproducibility (0.46) was moderate and repeatability (0.78) was good. Similar to human Achilles tendons, equine tendons were classified as predominantly hard using elastography. There was no statistically significant difference in stiffness of the flexor tendons (P = 0.96). No significant difference in stiffness was found with altered leg position during standing (P = 0.84) and while nonweight bearing (P = 0.61). The flexor tendons were softer when imaged in longitudinal versus transverse planes (P tendons and ligaments of the distal forelimb in horses. © 2013 American College of Veterinary Radiology.

  14. Minimally invasive, endoscopic Achilles tendon reconstruction using semitendinosus and gracilis tendons with Endobutton stabilization.

    Science.gov (United States)

    Piontek, Tomasz; Bąkowski, Paweł; Ciemniewska-Gorzela, Kinga; Grygorowicz, Monika

    2016-06-03

    Plantaris tendon, peronus brevis tendon and flexor hallucis longus tendon augmentation, commonly used in Achilles tendon rupture, often lead to weakening of injured foot and they require the immobilization after the surgery. It is essential to develop the technique, which gives no such limitation and allows for immediate functional improvement. We present our method of minimally invasive, endoscopic Achilles tendon reconstruction using semitendinosus and gracilis tendons with Endobutton stabilization. Posterolateral and posteromedial portals were made approximately 3 cm above the posterosuperior part of the calcaneus to clean the area of the Achilles tendon endoscopically. Then the hamstrings are harvested and prepared for the "Endobutton" system. A midline incision of the skin is performed approximately 1 cm above the posterosuperior part of the calcaneus to approach to the posterosuperior part of the calcaneus. Then under fluoroscopy the calcaneus was drilled through using K-wire. The distal end of the graft equipped with an Endobutton loop was entered into the drilled tunnel in the calcaneus. Later, 8 consecutive skin incisions are performed. Proximal ends of the graft were brought out through the native Achilles tendon reaching medial and lateral skin incisions. The final step was to transfer and tie the graft ends through the most proximal skin incision. This minimally invasive, endoscopic technique allows reconstruction of the Achilles tendon using semitendinosus and gracilis tendons with Endobutton stabilization and can be used in so-called "difficult", resistant cases as a "salvage procedure".

  15. Serial superficial digital flexor tendon biopsies for diagnosing and monitoring collagenase-induced tendonitis in horses

    Directory of Open Access Journals (Sweden)

    José C. de Lacerda Neto

    2013-06-01

    Full Text Available The purpose of this investigation was to demonstrate the feasibility of a biopsy technique by performing serial evaluations of tissue samples of the forelimb superficial digital flexor tendon (SDFT in healthy horses and in horses subjected to superficial digital flexor tendonitis induction. Eight adult horses were evaluated in two different phases (P, control (P1 and tendonitis-induced (P2. At P1, the horses were subjected to five SDFT biopsies of the left forelimb, with 24 hours (h of interval. Clinical and ultrasonographic (US examinations were performed immediately before the tendonitis induction, 24 and 48 h after the procedure. The biopsied tendon tissues were analyzed through histology. P2 evaluations were carried out three months later, when the same horses were subjected to tendonitis induction by injection of bacterial collagenase into the right forelimb SDFT. P2 clinical and US evaluations, and SDFT biopsies were performed before, and after injury induction at the following time intervals: after 24, 48, 72 and 96 h, and after 15, 30, 60, 90, 120 and 150 days. The biopsy technique has proven to be easy and quick to perform and yielded good tendon samples for histological evaluation. At P1 the horses did not show signs of localised inflammation, pain or lameness, neither SDFT US alterations after biopsies, showing that the biopsy procedure per se did not risk tendon integrity. Therefore, this procedure is feasible for routine tendon histological evaluations. The P2 findings demonstrate a relation between the US and histology evaluations concerning induced tendonitis evolution. However, the clinical signs of tendonitis poorly reflected the microscopic tissue condition, indicating that clinical presentation is not a reliable parameter for monitoring injury development. The presented method of biopsying SDFT tissue in horses enables the serial collection of material for histological analysis causing no clinical signs and tendon damage seen

  16. Blood flow and clearance in tendons. Studies with dogs.

    Science.gov (United States)

    Hooper, G; Davies, R; Tothill, P

    1984-05-01

    Blood flow in intact tendons in dogs was measured using 57Co-labelled microspheres and compared with the simultaneous clearance of a diffusible radionuclide, 85Sr, by the same tendons. Clearance was significantly greater than flow in all tendons, indicating that diffusion from surrounding tissues may be important in the nutrition of normal tendons.

  17. [Experimental study of allogenic tendon with sheath grafting in chicken].

    Science.gov (United States)

    Zhang, Y L; Wang, S L; Gao, X S

    2001-03-01

    To investigate availability of deep freeze stored allogenic tendon with sheath grafting in repairing the tendon and sheath defect in the II area of flexor digitorum tendon. Sixty chickens with tendon and sheath defect were divided into 2 groups randomly, group A was treated with allogenic grafting and group B was treated with autogenic grafting, these two groups were divided into two subgroups respectively, they were, group A1 allogenic tendon with whole sheath grafting, group A2 allogenic tendon with partial sheath grafting, group B1 autogenic tendon with whole sheath grafting and group B2 autogenic tendon with whole sheath grafting. All the allogenic grafts were treated by deep freeze. Histomorphological study, histoimmunological study and slipping function of the grafts were measured after operation. In group A1 and B1, the local reaction was sever, the nutrition of tendon graft was barricaded by the whole sheath resulting in adhesion, degeneration and necrosis. In group A2 and B2, the tendon graft healed well and little adhesion existed between tendon and sheath. The results showed that there were significant differences between tendon grafting with whole sheath and tendon grafting with partial sheath. Deep freeze store can reduce the immunogenicity of allogenic tendon with sheath. Allogenic tendon with partial sheath grafting can be used as a new biological material for repairing the tendon and sheath defect.

  18. Achilles tendon: US diagnosis of pathologic conditions. Work in progress

    Energy Technology Data Exchange (ETDEWEB)

    Blei, C.L.; Nirschl, R.P.; Grant, E.G.

    1986-06-01

    Twenty-three patients were prospectively examined with ultra-sound (US) for acute or recurrent Achilles tendon symptoms. Three types of pathologic conditions of the Achilles tendon were found: tendinitis/tenosynovitis, acute tendon trauma, and postoperative changes. US appears to enable differentiation of these conditions and to contribute to the diagnosis of a broad range of Achilles tendon disorders.

  19. Micromechanical properties and collagen composition of ruptured human achilles tendon

    DEFF Research Database (Denmark)

    Hansen, Philip; Kovanen, Vuokko; Hölmich, Per

    2013-01-01

    The Achilles tendon is one of the strongest tendons in the human body, and yet it frequently ruptures, which is a substantial clinical problem. However, the cause of ruptures remains elusive.......The Achilles tendon is one of the strongest tendons in the human body, and yet it frequently ruptures, which is a substantial clinical problem. However, the cause of ruptures remains elusive....

  20. Osmotic pressure induced tensile forces in tendon collagen

    Science.gov (United States)

    Masic, Admir; Bertinetti, Luca; Schuetz, Roman; Chang, Shu-Wei; Metzger, Till Hartmut; Buehler, Markus J.; Fratzl, Peter

    2015-01-01

    Water is an important component of collagen in tendons, but its role for the function of this load-carrying protein structure is poorly understood. Here we use a combination of multi-scale experimentation and computation to show that water is an integral part of the collagen molecule, which changes conformation upon water removal. The consequence is a shortening of the molecule that translates into tensile stresses in the range of several to almost 100 MPa, largely surpassing those of about 0.3 MPa generated by contractile muscles. Although a complete drying of collagen would be relevant for technical applications, such as the fabrication of leather or parchment, stresses comparable to muscle contraction already occur at small osmotic pressures common in biological environments. We suggest, therefore, that water-generated tensile stresses may play a role in living collagen-based materials such as tendon or bone.

  1. DYNAMIC SONOGRAPHY OF THE EQUINE METACARPO(TARSO)PHALANGEAL DIGITAL FLEXOR TENDON SHEATH.

    Science.gov (United States)

    DiGiovanni, Daria L; Rademacher, Nathalie; Riggs, Laura M; Baumruck, Rebecca A; Gaschen, Lorrie

    2016-11-01

    Palmar/plantar annular desmitis is a common disease that may be associated with adhesions and structures affecting the flexor tendons, which requires tenoscopy to diagnose. The purpose of this descriptive study was to develop a dynamic sonographic technique for evaluating the motion of normal equine flexor tendons in relation to the palmar/plantar annular ligament and to compare findings with horses previously diagnosed with palmar/plantar annular desmitis. Ten healthy adult horses were examined prospectively and the images of four horses diagnosed with palmar/plantar annular desmitis were retrospectively evaluated. Dynamic sonography was performed at the level of the metacarpo/metatarsophalangeal joint by maximally extending and flexing the interphalangeal joints. Palmar/plantar annular ligament thickness (mm), size of any gap between the flexor tendons, and subjectively increased angulation of the long linear echoes of the superficial digital flexor tendon were measured. The presence of gliding motion between the palmar/plantar annular ligament and superficial digital flexor tendon was determined by consensus. Twenty-eight healthy control limbs (16 hind/12 fore) and four with palmar/plantar annular desmitis (3 hind/1 fore) were evaluated. Controls had unrestricted gliding motion between the palmar/plantar annular ligament and flexor tendons and zero to 13° of angulation of the long linear echoes. The four affected horses had restricted gliding motion and between 20-35° angulation of the long linear echoes. Dynamic ultrasound is a feasible technique for detecting restricted flexor tendon and palmar/plantar annular ligament gliding motion, as well as subjectively increased angulation of the long linear echoes of the flexor tendon in affected horses compared with controls and warrants further investigation. © 2016 American College of Veterinary Radiology.

  2. Ultrasound elastography of the supraspinatus tendon guided by US-MRI virtual navigation.

    Science.gov (United States)

    Liu, Jun; Zhan, Weiwei; Zhou, Mingyang; Zhang, Xiaoxiao

    2015-01-01

    A virtual navigation system (VNS) can combine two imaging modalities for synchronous observation and can be beneficial for diagnosis and treatment. Ultrasound elastography (UE) can distinguish between soft and hard tissues. However, the application of UE to musculoskeletal structures is rare. To evaluate UE of the supraspinatus tendon using ultrasound-magnetic resonance imaging (US-MRI) virtual navigation. Sixty patients with an ache in the shoulder were diagnosed with supraspinatus tendon injuries using MRI. US-MRI virtual navigation was used to identify lesions in the supraspinatus tendon, and finally US elastography (UE) was performed. Volunteers whose supraspinatus tendons were diagnosed as normal by MRI were also selected for US elastography. The UE scores were then compared between patients and volunteers. A total of 60 patients were diagnosed with supraspinatus tendon injuries using MRI and forty-two patients classified as Grade I exhibited no obvious abnormality by US. The supraspinatus tendon injury scores were significantly higher in Grade I patients compared with volunteers (Pvirtual navigation.

  3. Patellar tendon rerupture in a footballer: our personal surgical technique and review of the literature.

    Science.gov (United States)

    Moretti, L; Vicenti, G; Abate, A; Pesce, V; Moretti, B

    2014-02-01

    Patellar tendon rerupture is a relatively uncommon condition that severely compromises the function of the extensor mechanism of the knee. Few cases described in the literature does not show a unique mode of treatment for this type of lesion. We report the case of a young athlete with traumatic patellar tendon rerupture. The first rupture was treated with the use of Statak anchors. Following a second rerupture incident as a result of a sporting accodent, the tendon was reconstructed with the use of an autologous graft tendon of semitendinosus and biological augmentation with gracilis tendon. For both tendons the distal insertion part was preserved to facilitate the healing process. The treatment was completed with the application of a neutralization cerclage wire and with local injection of plateket reach plasma (PRP). At 12 months follow up, a full recovery of the structure and function of the extensor mechanism was observed and the patient was able to resume normal sports competitive activity. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Delayed exercise promotes remodeling in sub-rupture fatigue damaged tendons.

    Science.gov (United States)

    Bell, R; Boniello, M R; Gendron, N R; Flatow, E L; Andarawis-Puri, N

    2015-06-01

    Tendinopathy is a common musculoskeletal injury whose treatment is limited by ineffective therapeutic interventions. Previously we have shown that tendons ineffectively repair early sub-rupture fatigue damage. In contrast, physiological exercise has been shown to promote remodeling of healthy tendons but its utility as a therapeutic to promote repair of fatigue damaged tendons remains unknown. Therefore, the objective of this study was to assess the utility of exercise initiated 1 and 14 days after onset of fatigue damage to promote structural repair in fatigue damaged tendons. We hypothesized that exercise initiated 14 days after fatigue loading would promote remodeling as indicated by a decrease in area of collagen matrix damage, increased procollagen I and decorin, while decreasing proteins indicative of tendinopathy. Rats engaged in 6-week exercise for 30 min/day or 60 min/day starting 1 or 14 days after fatigue loading. Initiating exercise 1-day after onset of fatigue injury led to exacerbation of matrix damage, particularly at the tendon insertion. Initiating exercise 14 days after onset of fatigue injury led to remodeling of damaged regions in the midsubstance and collagen synthesis at the insertion. Physiological exercise applied after the initial biological response to injury has dampened can potentially promote remodeling of damaged tendons. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  5. Living nanofiber yarn-based woven biotextiles for tendon tissue engineering using cell tri-culture and mechanical stimulation.

    Science.gov (United States)

    Wu, Shaohua; Wang, Ying; Streubel, Philipp N; Duan, Bin

    2017-10-15

    Non-woven nanofibrous scaffolds have been developed for tendon graft application by using electrospinning strategies. However, electrospun nanofibrous scaffolds face some obstacles and limitations, including suboptimal scaffold structure, weak tensile and suture-retention strengths, and compact structure for cell infiltration. In this work, a novel nanofibrous, woven biotextile, fabricated based on electrospun nanofiber yarns, was implemented as a tissue engineered tendon scaffold. Based on our modified electrospinning setup, polycaprolactone (PCL) nanofiber yarns were fabricated with reproducible quality, and were further processed into plain-weaving fabrics interlaced with polylactic acid (PLA) multifilaments. Nonwoven nanofibrous PCL meshes with random or aligned fiber structures were generated using typical electrospinning as comparative counterparts. The woven fabrics contained 3D aligned microstructures with significantly larger pore size and obviously enhanced tensile mechanical properties than their nonwoven counterparts. The biological results revealed that cell proliferation and infiltration, along with the expression of tendon-specific genes by human adipose derived mesenchymal stem cells (HADMSC) and human tenocytes (HT), were significantly enhanced on the woven fabrics compared with those on randomly-oriented or aligned nanofiber meshes. Co-cultures of HADMSC with HT or human umbilical vein endothelial cells (HUVEC) on woven fabrics significantly upregulated the functional expression of most tenogenic markers. HADMSC/HT/HUVEC tri-culture on woven fabrics showed the highest upregulation of most tendon-associated markers than all the other mono- and co-culture groups. Furthermore, we conditioned the tri-cultured constructs with dynamic conditioning and demonstrated that dynamic stretch promoted total collagen secretion and tenogenic differentiation. Our nanofiber yarn-based biotextiles have significant potential to be used as engineered scaffolds to

  6. Fibroma of the tendon sheath of the long head of the biceps tendon

    Energy Technology Data Exchange (ETDEWEB)

    Maeseneer, Michel de; Shahabpour, Maryam [Universitair Ziekenhuis Brussel, Department of Radiology, Brussels (Belgium); Isacker, Tom van [Sint-Lucas Hospital, Department of Orthopedic Surgery, Brugge (Belgium); Lenchik, Leon [Wake Forest School of Medicine, Department of Radiology, Winston Salem, NC (United States); Caillie, Marie-Astrid van [Sint-Lucas Hospital, Department of Pathology, Brugge (Belgium)

    2014-03-15

    Fibroma of the tendon sheath is a benign tumor that is less common than giant cell tumor of the tendon sheath. Both tumors may present as a painless, slowly enlarging mass. Radiological findings may be similar for both tumors. Histologically, fibroma of the tendon sheath lacks the hemosiderin-laden macrophages that are typical for giant cell tumor of the tendon sheath. We report on a 49-year-old woman with fibroma of the tendon sheath of the long head of the biceps tendon. In our case, on MR images, we observed band-like hypointense areas centrally in the tumor, mild patchy contrast enhancement, and most importantly, no decrease of signal intensity on gradient echo images. These characteristics reflected histological findings. (orig.)

  7. Nerve distributions in insertional Achilles tendinopathy - a comparison of bone, bursae and tendon.

    Science.gov (United States)

    Andersson, Gustav; Backman, Ludvig J; Christensen, Jens; Alfredson, Håkan

    2017-03-01

    In a condition of pain in the Achilles tendon insertion there are multiple structures involved, such as the Achilles tendon itself, the retrocalcaneal bursa and a bony protrusion at the calcaneal tuberosity called Haglund's deformity. The innervation patterns of these structures are scarcely described, and the subcutaneous calcaneal bursa is traditionally not considered to be involved in the pathology. This study aimed at describing the innervation patterns of the four structures described above to provide a better understanding of possible origins of pain at the Achilles tendon insertion. Biopsies were taken from 10 patients with insertional Achilles tendinopathy, which had pathological changes in the subcutaneous and retrocalcaneal bursae, a Haglund deformity and Achilles tendon tendinopathy as verified by ultrasound. The biopsies were stained using immunohistochemistry in order to delineate the innervation patterns in the structures involved in insertional Achilles tendinopathy. Immunohistochemical examinations found that the subcutaneous bursa scored the highest using a semi-quantitative evaluation of the degree of innervation when compared to the retrocalcaneal bursa, the Achilles tendon, and the calcaneal bone. These findings suggest that the subcutaneous bursa, which is traditionally not included in surgical treatment, may be a clinically important factor in insertional Achilles tendinopathy.

  8. Are the knee and ankle angles at contact related to the tendon properties of lower limbs in long distance runners?

    OpenAIRE

    Kubo, Keitaro; Miyazaki, Daisuke; Yamada, Kenji; Shimoju, Shozo; Tsunoda, Naoya

    2016-01-01

    The purpose of this study was to investigate whether the knee and ankle angles at contact during running were related to the elastic properties of tendon structures in knee extensors and plantar flexors and performance in trained long distance runners. Thirty-two highly trained male long distance runners participated in this study. Elongation of tendon structures in knee extensors and plantar flexors were measured using ultrasonography while subjects performed ramp isometric contractions up t...

  9. Finite Element Analysis of Grouting Compactness Monitoring in a Post-Tensioning Tendon Duct Using Piezoceramic Transducers

    Directory of Open Access Journals (Sweden)

    Tianyong Jiang

    2017-09-01

    Full Text Available With the development of the post-tensioning technique, prestressed concrete structures have been widely used in civil engineering. To ensure the long-term effectiveness of the prestressed tendon, the grouting quality of the tendon duct is one of the important factors. However, it is still a challenge to monitor the grouting quality of post-tensioning tendon ducts, due to the invisibility of the grouting. The authors’ previous work proposed a real-time method that employed a stress wave-based active sensing approach with piezoceramic transducers to monitor the grouting compactness of a Post-Tensioning Tendon Duct (PTTD. To further understand the piezoceramic induced stress wave propagation in the PTTD with different grouting levels, this paper develops a two-dimensional finite element model for monitoring the grouting compactness of the tendon duct with a piezoceramic transducer. A smart aggregate (SA developed to utilize one Lead Zirconate Titanate (PZT transducer with marble protection is installed in the center location of the tendon duct as an actuator. Two PZT patches are bonded on the bottom and top surface of the tendon duct as the sensors. The analysis results show that the finite element analysis results are in good agreement with the experimental results, which demonstrates that the finite element analysis is feasible and reliable. For the top half of the specimen, not much stress wave could be detected before the full grouting level, except for negligible signals that may propagate through the walls of the tendon duct. When the tendon duct grouting is at 100%, the stress wave propagates to the top of the specimen, and the displacements are symmetric in both left-right and top-bottom directions before the stress waves reach the boundary. The proposed two-dimensional finite element model has the potential to be implemented to simulate the stress wave propagation principle for monitoring grouting compaction of the post-tensioning tendon

  10. Tendon Is Covered by a Basement Membrane Epithelium That Is Required for Cell Retention and the Prevention of Adhesion Formation

    Science.gov (United States)

    Taylor, Susan H.; Al-Youha, Sarah; Van Agtmael, Tom; Lu, Yinhui; Wong, Jason; McGrouther, Duncan A.; Kadler, Karl E.

    2011-01-01

    The ability of tendons to glide smoothly during muscle contraction is impaired after injury by fibrous adhesions that form between the damaged tendon surface and surrounding tissues. To understand how adhesions form we incubated excised tendons in fibrin gels (to mimic the homeostatic environment at the injury site) and assessed cell migration. We noticed cells exiting the tendon from only the cut ends. Furthermore, treatment of the tendon with trypsin resulted in cell extravagation from the shaft of the tendons. Electron microscopy and immunolocalisation studies showed that the tendons are covered by a novel cell layer in which a collagen type IV/laminin basement membrane (BM) overlies a keratinised epithelium. PCR and western blot analyses confirmed the expression of laminin β1 in surface cells, only. To evaluate the cell retentive properties of the BM in vivo we examined the tendons of the Col4a1+/Svc mouse that is heterozygous for a G-to-A transition in the Col4a1 gene that produces a G1064D substitution in the α1(IV) chain of collagen IV. The flexor tendons had a discontinuous BM, developed fibrous adhesions with overlying tissues, and were acellular at sites of adhesion formation. In further experiments, tenotomy of wild-type mice resulted in expression of laminin throughout the adhesion. In conclusion, we show the existence of a novel tendon BM-epithelium that is required to prevent adhesion formation. The Col4a1+/Svc mouse is an effective animal model for studying adhesion formation because of the presence of a structurally-defective collagen type IV-containing BM. PMID:21298098

  11. Tendon is covered by a basement membrane epithelium that is required for cell retention and the prevention of adhesion formation.

    Directory of Open Access Journals (Sweden)

    Susan H Taylor

    2011-01-01

    Full Text Available The ability of tendons to glide smoothly during muscle contraction is impaired after injury by fibrous adhesions that form between the damaged tendon surface and surrounding tissues. To understand how adhesions form we incubated excised tendons in fibrin gels (to mimic the homeostatic environment at the injury site and assessed cell migration. We noticed cells exiting the tendon from only the cut ends. Furthermore, treatment of the tendon with trypsin resulted in cell extravagation from the shaft of the tendons. Electron microscopy and immunolocalisation studies showed that the tendons are covered by a novel cell layer in which a collagen type IV/laminin basement membrane (BM overlies a keratinised epithelium. PCR and western blot analyses confirmed the expression of laminin β1 in surface cells, only. To evaluate the cell retentive properties of the BM in vivo we examined the tendons of the Col4a1(+/Svc mouse that is heterozygous for a G-to-A transition in the Col4a1 gene that produces a G1064D substitution in the α1(IV chain of collagen IV. The flexor tendons had a discontinuous BM, developed fibrous adhesions with overlying tissues, and were acellular at sites of adhesion formation. In further experiments, tenotomy of wild-type mice resulted in expression of laminin throughout the adhesion. In conclusion, we show the existence of a novel tendon BM-epithelium that is required to prevent adhesion formation. The Col4a1(+/Svc mouse is an effective animal model for studying adhesion formation because of the presence of a structurally-defective collagen type IV-containing BM.

  12. Finite Element Analysis of Grouting Compactness Monitoring in a Post-Tensioning Tendon Duct Using Piezoceramic Transducers.

    Science.gov (United States)

    Jiang, Tianyong; Zheng, Junbo; Huo, Linsheng; Song, Gangbing

    2017-09-29

    With the development of the post-tensioning technique, prestressed concrete structures have been widely used in civil engineering. To ensure the long-term effectiveness of the prestressed tendon, the grouting quality of the tendon duct is one of the important factors. However, it is still a challenge to monitor the grouting quality of post-tensioning tendon ducts, due to the invisibility of the grouting. The authors' previous work proposed a real-time method that employed a stress wave-based active sensing approach with piezoceramic transducers to monitor the grouting compactness of a Post-Tensioning Tendon Duct (PTTD). To further understand the piezoceramic induced stress wave propagation in the PTTD with different grouting levels, this paper develops a two-dimensional finite element model for monitoring the grouting compactness of the tendon duct with a piezoceramic transducer. A smart aggregate (SA) developed to utilize one Lead Zirconate Titanate (PZT) transducer with marble protection is installed in the center location of the tendon duct as an actuator. Two PZT patches are bonded on the bottom and top surface of the tendon duct as the sensors. The analysis results show that the finite element analysis results are in good agreement with the experimental results, which demonstrates that the finite element analysis is feasible and reliable. For the top half of the specimen, not much stress wave could be detected before the full grouting level, except for negligible signals that may propagate through the walls of the tendon duct. When the tendon duct grouting is at 100%, the stress wave propagates to the top of the specimen, and the displacements are symmetric in both left-right and top-bottom directions before the stress waves reach the boundary. The proposed two-dimensional finite element model has the potential to be implemented to simulate the stress wave propagation principle for monitoring grouting compaction of the post-tensioning tendon duct.

  13. A Rare Case of Simultaneous Acute Bilateral Quadriceps Tendon Rupture and Unilateral Achilles Tendon Rupture

    OpenAIRE

    Wei Yee Leong; Daniel Gheorghiu; Janardhan Rao

    2013-01-01

    Introduction: There have been multiple reported cases of bilateral quadriceps tendon ruptures (QTR) in the literature. These injuries frequently associated with delayed diagnosis, which results in delayed surgical treatment. In very unusual cases, bilateral QTRs can be associated with other simultaneous tendon ruptures. Case Report: We present a rare case of bilateral QTR with a simultaneous Achilles Tendon Rupture involving a 31 years old Caucasian man who is a semi-professional body bui...

  14. Spatial organization and isotubulin composition of microtubules in epidermal tendon cells of Artemia franciscana.

    Science.gov (United States)

    Criel, Godelieve R J; Van Oostveldt, Patrick; MacRae, Thomas H

    2005-02-01

    Epidermally derived tendon cells attach the exoskeleton (cuticle) of the Branchiopod crustacean, Artemia franciscana, to underlying muscle in the hindgut, while the structurally similar transalar tendon (epithelial) cells, which also arise from the epidermis and are polarized, connect dorsal and ventral exopodite surfaces. To establish these latter attachments the transalar tendon cells interact with cuticles on opposite sides of the exopodite by way of their apical surfaces and with one another via basal regions, or the cuticle attachments may be mediated through linkages with phagocytic storage cells found in the hemolymph. In some cases, phyllopod tendon cells attach directly to muscle cells. Tendon cells in the hindgut of Artemia possess microtubule bundles, as do the transalar cells, and they extend from the basal myotendinal junction to the apical domain located near the cuticle. The bundled microtubules intermingle with thin filaments reminiscent of microfilaments, but intermediate filament-like structures are absent. Microtubule bundles converging at apical cell surfaces contact structures termed apical invaginations, composed of cytoplasmic membrane infoldings associated with electron-dense material. Intracuticular rods protrude from apical invaginations, either into the cuticle during intermolt or the molting fluid in premolt. Confocal microscopy of immunofluorescently stained samples revealed tyrosinated, detyrosinated, and acetylated tubulins, the first time posttranslationally modified isoforms of this protein have been demonstrated in crustacean tendon cells. Microfilaments, as shown by staining with phalloidin, coincided spatially with microtubule bundles. Artemia tendon cells clearly represent an interesting system for study of cytoskeleton organization within the context of cytoplasmic polarity and the results in this article indicate functional cooperation of microtubules and microfilaments. These cytoskeletal elements, either acting independently

  15. IMPINGEMENT-SYNDROME OF PERONEUS BREVIS TENDON AFTER CALCANEAL FRACTURES (MORPHOLOGICAL ASPECTS

    Directory of Open Access Journals (Sweden)

    N. S. Konovalchuk

    2017-01-01

    Full Text Available Background. One of the main causes of pain in patients with consequences of calcaneal fractures is the lateral impingement syndrome. This term means lateral displacement of outer calcaneal wall at the moment of fracture, narrowing of anatomical space under the lateral malleolus and compression of soft tissues in this region, including tendons of short and long peroneal muscles. This leads to chronic traumatization of tendons, alteration of their normal tracking and development of tendinitis and tenosynovitis. At this moment there are no articles in foreign or Russian literature describing how prolonged traumatization influences the internal structure of the tendons. The purpose of this study was to evaluate the morphological changes in structure of peroneus brevis tendon after different duration of compression between outer wall of calcaneus and the tip of the lateral malleolus in patients with calcaneal malunion.Materials and methods. Fifteen patients with calcaneal malunion and lateral impingement syndrome were treated operatively between 2016 and 2017. To confirm the lateral impingement syndrome, the authors performed clinical examination and AP x-rays of ankle joint. Two peroneus brevis tendon specimens were obtained intraoperatively in each of 15 patients: one specimen from compressed and one from non-compressed area. Obtained specimens were histologically examined according to standard protocol.Results. Microscopically all specimens showed separation of collagen bundles with loose connective tissue degeneration, increase of vascularization and inflammation. The degree of these changes differed according to the compression duration. This allowed us to analyze the dynamics of these changes.Conclusion. The morphological changes in structure of peroneus brevis tendon during the compression between outer wall of calcaneus and the tip of the lateral malleolus correspond with dynamics of common pathologic reactions. Early stages showed signs of

  16. Assessment of Postoperative Tendon Quality in Patients With Achilles Tendon Rupture Using Diffusion Tensor Imaging and Tendon Fiber Tracking.

    Science.gov (United States)

    Sarman, Hakan; Atmaca, Halil; Cakir, Ozgur; Muezzinoglu, Umit Sefa; Anik, Yonca; Memisoglu, Kaya; Baran, Tuncay; Isik, Cengiz

    2015-01-01

    Although pre- and postoperative imaging of Achilles tendon rupture (ATR) has been well documented, radiographic evaluations of postoperative intratendinous healing and microstructure are still lacking. Diffusion tensor imaging (DTI) is an innovative technique that offers a noninvasive method for describing the microstructure characteristics and organization of tissues. DTI was used in the present study for quantitative assessment of fiber continuity postoperatively in patients with acute ATR. The data from 16 patients with ATR from 2005 to 2012 were retrospectively analyzed. The microstructure of ART was evaluated using tendon fiber tracking, tendon continuity, fractional anisotropy, and apparent diffusion coefficient values by way of DTI. The distal and proximal portions were measured separately in both the ruptured and the healthy extremities of each patient. The mean patient age was 41.56 ± 8.49 (range 26 to 56) years. The median duration of follow-up was 21 (range 6 to 80) months. The tendon fractional anisotropy values of the ruptured Achilles tendon were significantly lower statistically than those of the normal side (p = .001). However, none of the differences between the 2 groups with respect to the distal and proximal apparent diffusion coefficient were statistically significant (p = .358 and p = .899, respectively). In addition, the fractional anisotropy and apparent diffusion coefficient measurements were not significantly different in the proximal and distal regions of the ruptured tendons compared with the healthy tendons. The present study used DTI and fiber tracking to demonstrate the radiologic properties of postoperative Achilles tendons with respect to trajectory and tendinous fiber continuity. Quantifying DTI and fiber tractography offers an innovative and effective tool that might be able to detect microstructural abnormalities not appreciable using conventional radiologic techniques. Copyright © 2015 American College of Foot and Ankle

  17. A Biomechanical Study of a Novel Asymmetric 6-Strand Flexor Tendon Repair Using Porcine Tendons.

    Science.gov (United States)

    Wong, Yoke Rung; Tay, Shian Chao

    2018-01-01

    This study evaluated the biomechanical performance of a novel asymmetric 6-strand flexor tendon repair technique without locking loops. Twenty porcine flexor tendons were equally repaired by using the asymmetric technique and compared with the modified Lim-Tsai repair technique. The ultimate tensile strength, load to 1-mm gap force, stiffness, and mechanism of failure were measured. The asymmetric repair technique had significantly higher tensile strength (63.3 ± 3.7 N) than the modified Lim-Tsai repairs (46.7 ± 8.3 N). A novel flexor tendon repair technique with improved biomechanical performance may be available for use in flexor tendon repairs.

  18. Transcription factor EGR1 directs tendon differentiation and promotes tendon repair

    National Research Council Canada - National Science Library

    Guerquin, Marie-Justine; Charvet, Benjamin; Nourissat, Geoffroy; Havis, Emmanuelle; Ronsin, Olivier; Bonnin, Marie-Ange; Ruggiu, Mathilde; Olivera-Martinez, Isabel; Robert, Nicolas; Lu, Yinhui; Kadler, Karl E; Baumberger, Tristan; Doursounian, Levon; Berenbaum, Francis; Duprez, Delphine

    2013-01-01

    Tendon formation and repair rely on specific combinations of transcription factors, growth factors, and mechanical parameters that regulate the production and spatial organization of type I collagen...

  19. Targeted Deletion of Collagen V in Tendons and Ligaments Results in a Classic Ehlers-Danlos Syndrome Joint Phenotype

    Science.gov (United States)

    Sun, Mei; Connizzo, Brianne K.; Adams, Sheila M.; Freedman, Benjamin R.; Wenstrup, Richard J.; Soslowsky, Louis J.; Birk, David E.

    2016-01-01

    Collagen V mutations underlie classic Ehlers-Danlos syndrome, and joint hypermobility is an important clinical manifestation. We define the function of collagen V in tendons and ligaments, as well as the role of alterations in collagen V expression in the pathobiology in classic Ehlers-Danlos syndrome. A conditional Col5a1flox/flox mouse model was bred with Scleraxis-Cre mice to create a targeted tendon and ligament Col5a1-null mouse model, Col5a1Δten/Δten. Targeting was specific, resulting in collagen V–null tendons and ligaments. Col5a1Δten/Δten mice demonstrated decreased body size, grip weakness, abnormal gait, joint laxity, and early-onset osteoarthritis. These gross changes were associated with abnormal fiber organization, as well as altered collagen fibril structure with increased fibril diameters and decreased fibril number that was more severe in a major joint stabilizing ligament, the anterior cruciate ligament (ACL), than in the flexor digitorum longus tendon. The ACL also had a higher collagen V content than did the flexor digitorum longus tendon. The collagen V–null ACL and flexor digitorum longus tendon both had significant alterations in mechanical properties, with ACL exhibiting more severe changes. The data demonstrate critical differential regulatory roles for collagen V in tendon and ligament structure and function and suggest that collagen V regulatory dysfunction is associated with an abnormal joint phenotype, similar to the hypermobility phenotype in classic Ehlers-Danlos syndrome. PMID:25797646

  20. Traumatic tibialis anterior tendon rupture: treatment with a two-stage silicone tube and an interposition hamstring tendons graft protocol.

    Science.gov (United States)

    Kontogeorgakos, Vasileios; Koutalos, Antonios; Hantes, Michael; Manoudis, Gregory; Badras, Leonidas; Malizos, Konstantinos

    2015-03-01

    A novel technique for managing ruptured tibialis anterior tendon complicated by infection and tendon substance loss in a young adult is described. A two-stage reconstruction technique with a silicon tube and tendon autograft was performed. At first, after local control of the infection, scar excision and placement of a silicone tube was performed. Ten weeks later, ipsilateral hamstrings tendons were harvested and bridged the 7 cm tendon gap. Eighteen months later, the patient has excellent clinical and functional outcome.

  1. Combination of biochemical and mechanical cues for tendon tissue engineering.

    Science.gov (United States)

    Testa, Stefano; Costantini, Marco; Fornetti, Ersilia; Bernardini, Sergio; Trombetta, Marcella; Seliktar, Dror; Cannata, Stefano; Rainer, Alberto; Gargioli, Cesare

    2017-11-01

    Tendinopathies negatively affect the life quality of millions of people in occupational and athletic settings, as well as the general population. Tendon healing is a slow process, often with insufficient results to restore complete endurance and functionality of the tissue. Tissue engineering, using tendon progenitors, artificial matrices and bioreactors for mechanical stimulation, could be an important approach for treating rips, fraying and tissue rupture. In our work, C3H10T1/2 murine fibroblast cell line was exposed to a combination of stimuli: a biochemical stimulus provided by Transforming Growth Factor Beta (TGF-β) and Ascorbic Acid (AA); a three-dimensional environment represented by PEGylated-Fibrinogen (PEG-Fibrinogen) biomimetic matrix; and a mechanical induction exploiting a custom bioreactor applying uniaxial stretching. In vitro analyses by immunofluorescence and mechanical testing revealed that the proposed combined approach favours the organization of a three-dimensional tissue-like structure promoting a remarkable arrangement of the cells and the neo-extracellular matrix, reflecting into enhanced mechanical strength. The proposed method represents a novel approach for tendon tissue engineering, demonstrating how the combined effect of biochemical and mechanical stimuli ameliorates biological and mechanical properties of the artificial tissue compared to those obtained with single inducement. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  2. Condition Assessment of PC Tendon Duct Filling by Elastic Wave Velocity Mapping

    Directory of Open Access Journals (Sweden)

    Kit Fook Liu

    2014-01-01

    Full Text Available Imaging techniques are high in demand for modern nondestructive evaluation of large-scale concrete structures. The travel-time tomography (TTT technique, which is based on the principle of mapping the change of propagation velocity of transient elastic waves in a measured object, has found increasing application for assessing in situ concrete structures. The primary aim of this technique is to detect defects that exist in a structure. The TTT technique can offer an effective means for assessing tendon duct filling of prestressed concrete (PC elements. This study is aimed at clarifying some of the issues pertaining to the reliability of the technique for this purpose, such as sensor arrangement, model, meshing, type of tendon sheath, thickness of sheath, and material type as well as the scale of inhomogeneity. The work involved 2D simulations of wave motions, signal processing to extract travel time of waves, and tomography reconstruction computation for velocity mapping of defect in tendon duct.

  3. Position Control of Tendon-Driven Fingers

    Science.gov (United States)

    Abdallah, Muhammad E.; Platt, Robert, Jr.; Hargrave, B.; Pementer, Frank

    2011-01-01

    Conventionally, tendon-driven manipulators implement some force control scheme based on tension feedback. This feedback allows the system to ensure that the tendons are maintained taut with proper levels of tensioning at all times. Occasionally, whether it is due to the lack of tension feedback or the inability to implement sufficiently high stiffnesses, a position control scheme is needed. This work compares three position controllers for tendon-driven manipulators. A new controller is introduced that achieves the best overall performance with regards to speed, accuracy, and transient behavior. To compensate for the lack of tension feedback, the controller nominally maintains the internal tension on the tendons by implementing a two-tier architecture with a range-space constraint. These control laws are validated experimentally on the Robonaut-2 humanoid hand. I

  4. PERONEAL TENDON LESIONS IN ATHLETES (REVIEW)

    National Research Council Canada - National Science Library

    E. E. Achkasov; A. P. Sereda; A. D. Repetyuk

    2016-01-01

    .... Peroneal tendons pathology is not the major but the underestimated cause of pain in lateral and hindfoot as well as of foot dysfunction which is difficult to distinguish from lesions of lateral...

  5. Terminology for Achilles tendon related disorders

    NARCIS (Netherlands)

    van Dijk, C. N.; van Sterkenburg, M. N.; Wiegerinck, J. I.; Karlsson, J.; Maffulli, N.

    2011-01-01

    The terminology of Achilles tendon pathology has become inconsistent and confusing throughout the years. For proper research, assessment and treatment, a uniform and clear terminology is necessary. A new terminology is proposed; the definitions hereof encompass the anatomic location, symptoms,

  6. Is sonoelastography of value in assessing tendons?

    Science.gov (United States)

    Klauser, Andrea S; Faschingbauer, Ralph; Jaschke, Werner R

    2010-09-01

    Sonoelastography is a newly introduced ultrasound technique that evaluates tissue elasticity and thus provides additional information to that offered by conventional ultrasound images. In the musculoskeletal field, sonoelastography can help improve estimation of tendon stiffness. In this article, the principles and future developments of sonoelastography are discussed using the strongest and thickest tendon of the human body, the Achilles tendon, for illustrative purposes. Preliminary findings of sonoelastography in healthy and pathological Achilles tendons, technical considerations, examination technique and several limitations are addressed. The usefulness of elastography can be expected to increase rapidly in the musculoskeletal field, as soon as we learn to interpret elastographic artifacts as well as to take advantage of the new information provided by sonoelastography. Thieme Medical Publishers.

  7. Jumper's Knee (Patellar Tendonitis) (For Parents)

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Jumper's Knee (Patellar Tendonitis) KidsHealth / For Parents / Jumper's Knee (Patellar ... prevent continued damage to the knee. How the Knee Works To understand how jumper's knee happens, it ...

  8. Achilles tendon assessed with sonoelastography: histologic agreement

    National Research Council Canada - National Science Library

    Klauser, Andrea S; Miyamoto, Hideaki; Tamegger, Mario; Faschingbauer, Ralph; Moriggl, Bernhard; Klima, Guenther; Feuchtner, Gudrun M; Kastlunger, Martin; Jaschke, Werner R

    2013-01-01

    ...) and sonoelastography of the Achilles tendon with findings at histologic assessment. This study was conducted with the approval of the institutional review boards, and all cadavers were in legal custody of the study institution...

  9. Identification of a Remodeled Neo-tendon After Arthroscopic Latarjet Procedure.

    Science.gov (United States)

    Smolen, Daniel; Went, Philip; Tomala, Dirk; Sternberg, Christoph; Lafosse, Laurent; Leuzinger, Jan

    2017-03-01

    To macroscopically, histologically, and radiologically describe a time-dependent remodeling process of a neo-tendon or -ligament in the shoulder after the arthroscopic Latarjet procedure. During follow-up surgery after the arthroscopic Latarjet procedure, 17 shoulders in 16 patients were evaluated for a remodeled tendon-like structure. The mean overall follow-up period was 27.4 months. The mean time between the arthroscopic Latarjet procedure and revision was 11.6 months. All shoulders were evaluated with magnetic resonance imaging, and seven histologic specimens were obtained during revision surgery. A distinct, oriented strand of tissue was found in 16 of 17 shoulders on revision surgery. Postoperative magnetic resonance imaging analyses showed a signal-free, longitudinal tendon-like structure originating at the tip of the acromion, traversing the space of the former subcoracoid bursa to attach in the course of the transposed conjoint tendon or the proximal short head of the biceps. Histologic analysis of seven specimens showed a characteristic timeline of remodeling. A tendon- or ligament-like structure is remodeled between the anterior bottom tip of the acromion and the transposed coracoid process in a time-dependent manner after the arthroscopic Latarjet procedure. Level IV, therapeutic case series. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  10. Early diagnosis of tendon pathologies with sonoelastography

    OpenAIRE

    Zeynep ilerisoy Yakut; Torel Ogur; sukran Erten; Deniz Delibas; Meltem Yildirim; Halil Arslan; Mehmet Gumus

    2015-01-01

    AIM : Sonoelastography (SE) is a new ultrasound-based imaging technique that provides information on tissue elasticity and stiffness. Strain sonoelastography is the most commonly used technique that allows real-time visualisation of the tissue. In this study, we searched the efficacy of SE for assessing Achilles tendon abnormalities in patients with familial mediterranean fever (FMF) suffering from talalgia. METHODS: Achilles tendons of 18 FMF patients suffering from unilateral talala...

  11. Suitable long tendon technologies and practices

    CSIR Research Space (South Africa)

    Altounyan, P

    2001-10-01

    Full Text Available to improve safety in coal mines. In order to improve safety in South African coal mining operations it is essential that rock engineering and support practices be improved in the light of available international knowledge and best practice... and Practices 2 1. The introduction of safer and more effective long tendon support systems. 2. The development of an industry wide guidance documents for each long tendon support type to be used. 3. The identification of appropriate laboratory...

  12. Tendon rupture associated with excessive smartphone gaming.

    Science.gov (United States)

    Gilman, Luke; Cage, Dori N; Horn, Adam; Bishop, Frank; Klam, Warren P; Doan, Andrew P

    2015-06-01

    Excessive use of smartphones has been associated with injuries. A 29-year-old, right hand-dominant man presented with chronic left thumb pain and loss of active motion from playing a Match-3 puzzle video game on his smartphone all day for 6 to 8 weeks. On physical examination, the left extensor pollicis longus tendon was not palpable, and no tendon motion was noted with wrist tenodesis. The thumb metacarpophalangeal range of motion was 10° to 80°, and thumb interphalangeal range of motion was 30° to 70°. The clinical diagnosis was rupture of the left extensor pollicis longus tendon. The patient subsequently underwent an extensor indicis proprius (1 of 2 tendons that extend the index finger) to extensor pollicis longus tendon transfer. During surgery, rupture of the extensor pollicis longus tendon was seen between the metacarpophalangeal and wrist joints. The potential for video games to reduce pain perception raises clinical and social considerations about excessive use, abuse, and addiction. Future research should consider whether pain reduction is a reason some individuals play video games excessively, manifest addiction, or sustain injuries associated with video gaming.

  13. TREATMENT OF OLD ACHILLES TENDON RUPTURES

    Directory of Open Access Journals (Sweden)

    N. A. Koryshkov

    2012-01-01

    Full Text Available From 1998 to 2010 32 patients (14 men, 18 women, aged 15-65 years, underwent surgical treatment for old Achilles tendon rupture. In all cases correct diagnosis was made not earlier than 1 month after injury. The importance of clinical Thompson test and sonographic examination for diagnosis of Achilles tendon rupture is underlined. For the restoration of Achilles tendon V-Y plasty was used. Surgery was performed in a period of 1 to 13 months in patients with subcutaneous Achilles tendon ruptures. Follow-up results of patients in the postoperative period ranged from 6 months to 10 years (mean follow-up 1 year 7 months. Date of observation in the postoperative period ranged from 6 months to 19 years. Marginal necrosis wound occurred in 3 (10% patients, re-rupture of the Achilles tendon to tendon suture zone - in one patient, even in one patient on day 14 became infected. Violations of the foot innervation were no detected.

  14. Triceps tendon rupture: repair and rehabilitation.

    Science.gov (United States)

    Kocialkowski, Cezary; Carter, Rebecca; Peach, Chris

    2018-01-01

    Triceps tendon ruptures are rare injuries and are frequently missed on initial presentation to the emergency department. In cases of complete rupture, surgical repair is recommended but no guidelines exist on the optimum reconstructive technique or rehabilitation. We present a surgical technique and rehabilitation programme for the management of these injuries. A midline posterior incision is performed, the ruptured triceps tendon is identified and mobilized, and the tendon footprint is prepared. The tendon is then repaired using bone suture anchors, with a parachute technique, and held in 40° of flexion. The rehabilitation programme is divided into five phases, over a period of 12 weeks. Range of movement is gradually increased in a brace for the first 6 weeks. Rehabilitation is gradually increase in intensity, progressing from isometric extension exercises to weight-resisted exercises, and finally plyometrics and throwing exercises. Our surgical technique provides a solid tendon repair without the need for further metalwork removal. The graduated rehabilitation programme also helps to protect the integrity of the repair at the same time as enabling patients to gradually increase the strength of the triceps tendon and ultimately return to sport activities.

  15. Arthroscopic quadriceps tendon repair: two case reports.

    Science.gov (United States)

    Saito, Hidetomo; Shimada, Yoichi; Yamamura, Toshiaki; Yamada, Shin; Sato, Takahiro; Nozaka, Koji; Kijima, Hiroaki; Saito, Kimio

    2015-01-01

    Recently, although some studies of open repair of the tendon of the quadriceps femoris have been published, there have been no reports in the literature on primary arthroscopic repair. In our present study, we present two cases of quadriceps tendon injury arthroscopically repaired with excellent results. Case 1 involved a 68-year-old man who was injured while shifting his weight to prevent a fall. MRI showed complete rupture at the insertion of the patella of the quadriceps tendon. The rupture was arthroscopically repaired using both suture anchor and pull-out suture fixation methods via bone tunnels (hereafter, pull-out fixation). Two years after surgery, retearing was not observed on MRI and both Japan Orthopedic Association (JOA) Knee and Lysholm scores had recovered to 100. Case 2 involved a 50-year-old man who was also injured when shifting his weight to prevent a fall. MRI showed incomplete superficial rupture at the insertion of the patella of the quadriceps tendon. The rupture was arthroscopically repaired using pull-out fixation of six strand sutures. One year after surgery, MRI revealed a healed tendon and his JOA and Lysholm scores were 95 and 100, respectively. Thus, arthroscopic repair may be a useful surgical method for repairing quadriceps tendon injury.

  16. Arthroscopic Quadriceps Tendon Repair: Two Case Reports

    Directory of Open Access Journals (Sweden)

    Hidetomo Saito

    2015-01-01

    Full Text Available Recently, although some studies of open repair of the tendon of the quadriceps femoris have been published, there have been no reports in the literature on primary arthroscopic repair. In our present study, we present two cases of quadriceps tendon injury arthroscopically repaired with excellent results. Case 1 involved a 68-year-old man who was injured while shifting his weight to prevent a fall. MRI showed complete rupture at the insertion of the patella of the quadriceps tendon. The rupture was arthroscopically repaired using both suture anchor and pull-out suture fixation methods via bone tunnels (hereafter, pull-out fixation. Two years after surgery, retearing was not observed on MRI and both Japan Orthopedic Association (JOA Knee and Lysholm scores had recovered to 100. Case 2 involved a 50-year-old man who was also injured when shifting his weight to prevent a fall. MRI showed incomplete superficial rupture at the insertion of the patella of the quadriceps tendon. The rupture was arthroscopically repaired using pull-out fixation of six strand sutures. One year after surgery, MRI revealed a healed tendon and his JOA and Lysholm scores were 95 and 100, respectively. Thus, arthroscopic repair may be a useful surgical method for repairing quadriceps tendon injury.

  17. Improving the state of the art in FEM analysis of PCCVs with bonded and unbonded prestress tendons

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Christopher A., E-mail: cajone@sandia.gov [Sandia National Laboratories, PO Box 5800, MS 0744, Albuquerque, NM 87125-0744 (United States); Dameron, Robert, E-mail: rdameron@moffattnichol.com [Moffatt and Nichol, 1660 Hotel Cir N, San Diego, CA 92108 (United States); Sircar, Madhumita, E-mail: Madhumita.sircar@nrc.gov [U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001 (United States)

    2015-12-15

    Highlights: • A novel method for FE modeling of bonded and unbonded tendons was developed. • Bonded and unbonded tendon models were compared for use in PCCVs. • For internal overpressurization, unbonded tendons perform slightly better. • Tendon slip and load redistribution are credited for the increased performance. - Abstract: In order to assess the structural performance of grouted prestressing systems in nuclear power containment vessels, a full containment vessel was modeled using the finite element program, ABAQUS. Both bonded (grouted) and unbonded (ungrouted) prestressing systems were modeled. Prior to simulation of grouting, both models were identical, with the prestressing stages modeled explicitly, and friction represented along the tendons. The results indicate higher peak stresses and strains in the bonded model since the tendon system is not permitted to slip and redistribute forces as the vessel deforms. Correspondingly, it is noted that the analysis predicts failure of the vessel at a lower internal pressure in the case of the bonded system. This work is an extension of a collaborative study of finite element analysis (FEA) of prestressed concrete containment vessels (PCCVs) sponsored by the United States Nuclear Regulatory Commission (USNRC) and the Atomic Energy Regulatory Board (AERB) of India. Particular emphasis was placed on advancing the state of the art in modeling tendons (Akin et al., 2013a; Heitman et al., 2014).

  18. Viscoelastic Properties of Healthy Achilles Tendon are Independent of Isometric Plantar Flexion Strength and Cross-Sectional Area

    Science.gov (United States)

    Suydam, Stephen M.; Soulas, Elizabeth M.; Elliott, Dawn M.; Silbernagel, Karin Gravare; Buchanan, Thomas S.; Cortes, Daniel H.

    2015-01-01

    Changes in tendon viscoelastic properties are observed after injuries and during healing as a product of altered composition and structure. Continuous Shear Wave Elastography is a new technique measuring viscoelastic properties of soft tissues using external shear waves. Tendon has not been studied with this technique, therefore, the aims of this study were to establish the range of shear and viscosity moduli in healthy Achilles tendons, determine bilateral differences of these parameters and explore correlations of viscoelasticity to plantar flexion strength and tendon area. Continuous Shear Wave Elastography was performed over the free portion of both Achilles tendons from 29 subjects. Isometric plantar flexion strength and cross sectional area were measured. The average shear and viscous moduli was 83.2kPa and 141.0Pa-s, respectively. No correlations existed between the shear or viscous modulus and area or strength. This indicates that viscoelastic properties can be considered novel, independent biomarkers. The shear and viscosity moduli were bilaterally equivalent (p=0.013,0.017) which allows determining pathologies through side-to-side deviations. The average bilateral coefficient of variation was 7.2% and 9.4% for shear and viscosity modulus, respectively. The viscoelastic properties of the Achilles tendon may provide an unbiased, non-subjective rating system of tendon recovery and optimizing treatment strategies. PMID:25882209

  19. [Treatment of unrecent patellar tendon tear with semitendinous and gracilis tendons].

    Science.gov (United States)

    Estrada-Malacón, C A; García-Estrada, G A

    2011-01-01

    The patellar tendon lesion is very important due to the role of this tendon on the conformation of the extensor mechanism of the quadriceps. When the terminal end of this mechanism is injured, the extensor function of the knee is completely lost and thus the functional capability of the involved limb is completely disrupted.

  20. Local trauma in human patellar tendon leads to widespread changes in the tendon gene expression

    DEFF Research Database (Denmark)

    Heinemeier, Katja Maria; Lorentzen, Marc P; Kildevang Jensen, Jacob

    2016-01-01

    of Insulin-like growth factor-I, connective tissue growth factor, scleraxis, decorin, fibromodulin, tenascin-C, tenomodulin, VEGFa, CD68, IL-6, MMP12 and MMP13. In conclusion, a moderate trauma to a healthy human tendon (e.g. biopsy sampling) results in a widespread up-regulation of tendon cell activity...

  1. Mechanical Properties of Human Patellar Tendon at the Hierarchical levels of Tendon and Fibril

    DEFF Research Database (Denmark)

    Svensson, Rene Brüggebusch; Hansen, Philip; Hassenkam, Tue

    2012-01-01

    that of tendon supports that fibrillar rather than interfibrillar properties govern sub-failure tendon response, making the fibrillar level a meaningful target of intervention. The lower modulus found in vitro suggests a possible adverse effect of removing the tissue from its natural environment. In addition...

  2. Depiction of Achilles Tendon Microstructure In-Vivo Using High-Resolution 3D Ultrashort Echo-Time MRI at 7T

    Science.gov (United States)

    Han, Misung; Larson, Peder E. Z.; Liu, Jing; Krug, Roland

    2014-01-01

    Objectives To demonstrate the feasibility of depicting the internal structure of the Achilles tendon in vivo using high-resolution 3D ultrashort echo-time (UTE) magnetic resonance imaging (MRI) at 7T. Materials and Methods For our UTE imaging, a minimum-phase radiofrequency pulse and an anisotropic field-of-view 3D radial acquisition were used to minimize the echo time and scan time. A fat saturation pulse was applied every eight spoke acquisitions to reduce blurring and chemical shift artifacts from fat and to improve dynamic range of the tendon signal. Five healthy volunteers and one patient were scanned with an isotropic spatial resolution of up to 0.6 mm. Fat-suppressed UTE images were qualitatively evaluated and compared to non-fat-suppressed UTE images and longer echo-time images. Results High-resolution UTE imaging was able to visualize the microstructure of the Achilles tendon. Fat suppression substantially improved the depiction of the internal structure. The UTE images revealed a fascicular pattern in the Achilles tendon and fibrocartilage at the tendon insertion. In a patient who had tendon elongation surgery after birth there was clear depiction of disrupted tendon structure. Conclusions High-resolution fat-suppressed 3D UTE imaging at 7T allows for evaluation of the Achilles tendon microstructure in vivo. PMID:24500089

  3. Mechanical properties of the human Achilles tendon, in vivo

    DEFF Research Database (Denmark)

    Kongsgaard, M; Nielsen, C H; Hegnsvad, S

    2011-01-01

    Ultrasonography has been widely applied for in vivo measurements of tendon mechanical properties. Assessments of human Achilles tendon mechanical properties have received great interest. Achilles tendon injuries predominantly occur in the tendon region between the Achilles-soleus myotendinous...... junction and Achilles-calcaneus osteotendinous junction i.e. in the free Achilles tendon. However, there has been no adequate ultrasound based method for quantifying the mechanical properties of the free human Achilles tendon. This study aimed to: 1) examine the mechanical properties of the free human...

  4. Lower Robotic Arm Assembly Having a Plurality of Tendon Driven Digits

    Science.gov (United States)

    Guo, Raymond (Inventor); Bridgwater, Lyndon (Inventor); Nguyen, Vienny (Inventor); Radford, Nicolaus A. (Inventor)

    2016-01-01

    A lower robotic arm includes a base structure, a plurality of digits, and a plurality of tendons. The digits each include first, second, third, and fourth phalanges. Each digit is operatively attached to the base structure at the respective first phalange. A first joint operatively connects the first and second phalange to define a first axis, a second operatively connects the second and third phalange to define a second axis, and a third joint operatively connects the third and fourth phalange to define a third axis, such that the phalanges are selectively rotatable relative to the adjacent phalange, about the respective axis. The tendons are operatively connected to a respective one of the fourth phalanges. Each tendon selectively applies a first torque to the respective fourth phalange to urge the respective phalanges to rotate in a first direction about the respective axes.

  5. Flexor tendon tissue engineering: acellularization of human flexor tendons with preservation of biomechanical properties and biocompatibility.

    Science.gov (United States)

    Pridgen, Brian C; Woon, Colin Y L; Kim, Maxwell; Thorfinn, Johan; Lindsey, Derek; Pham, Hung; Chang, James

    2011-08-01

    Acellular human tendons are a candidate scaffold for tissue engineering flexor tendons of the hand. This study compared acellularization methods and their compatibility with allogeneic human cells. Human flexor tendons were pretreated with 0.1% ethylenediaminetetracetic acid (EDTA) for 4  h followed by 24  h treatments of 1% Triton X-100, 1% tri(n-butyl)phosphate, or 0.1% or 1% sodium dodecyl sulfate (SDS) in 0.1% EDTA. Outcomes were assessed histologically by hematoxylin and eosin and SYTO green fluorescent nucleic acid stains and biochemically by a QIAGEN DNeasy kit, Sircol collagen assay, and 1,9 dimethylmethylene blue glycosaminoglycan assay. Mechanical data were collected using a Materials Testing System to pull to failure tendons acellularized with 0.1% SDS. Acellularized tendons were re-seeded in a suspension of human dermal fibroblasts. Attachment of viable cells to acellularized tendon was assessed biochemically by a cell viability assay and histologically by a live/dead stain. Data are reported as mean±standard deviation. Compared with the DNA content of fresh tendons (551±212  ng DNA/mg tendon), only SDS treatments significantly decreased DNA content (1% SDS [202.8±37.4  ng DNA/mg dry weight tendon]; 0.1% SDS [189±104  ng DNA/mg tendon]). These findings were confirmed by histology. There was no decrease in glycosaminoglycans or collagen following acellularization with SDS. There was no difference in the ultimate tensile stress (55.3±19.2 [fresh] vs. 51.5±6.9 [0.1% SDS] MPa). Re-seeded tendons demonstrated attachment of viable cells to the tendon surface using a viability assay and histology. Human flexor tendons were acellularized with 0.1% SDS in 0.1% EDTA for 24  h with preservation of mechanical properties. Preservation of collagen and glycoaminoglycans and re-seeding with human cells suggest that this scaffold is biocompatible. This will provide a promising scaffold for future human flexor tendon tissue engineering studies to

  6. Local administration of Trolox, a vitamin E analog, reduced tendon adhesion in a chicken model of flexor digitorum profundus tendon injury

    OpenAIRE

    Lee, Yuk Wa; Fu, Sai Chuen; Mok, Tsui Yu; Chan, Kai Ming; Hung, Leung Kim

    2016-01-01

    Background: Hand flexor tendon injuries are compromised with tendon adhesion. Tendon adhesion forms between flexor tendon and tendon sheath, reduces the range of motion of fingers, and affects their function. Oxidative stress is increased in flexor tendon after injury and might play a role in tendon adhesion formation. Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), a water-soluble analog of vitamin E, is antioxidative. Trolox reduced oxidative stress and the expression of fi...

  7. Management of acute Achilles tendon rupture with tendon-bundle technique.

    Science.gov (United States)

    Li, Chun-Guang; Li, Bing; Yang, Yun-Feng

    2017-02-01

    Objective * These authors contributed equally to this work. To explore tendon-bundle technique for treating Achilles tendon rupture with no defects. Methods Patients with full unilateral Achilles tendon rupture with no defects were included. The Achilles tendon medial edge surgical repair approach was used, revealing horsetail-like rupture bundles. Tendon bundles were anatomically realigned and repaired end-to-end using 5-0 sutures. Patients were followed-up for 1 year, and assessed for differences between the repaired versus healthy limb. Results Out of 24 patients (18 male, 6 female; aged 19-56 years) at 1 year following surgery, mean American Orthopaedic Foot and Ankle Society score was 92.4 ± 5.9; mean differences between the surgically repaired versus contralateral side in dorsiflexion and plantarflexion angle were 3.5 ± 2.3° and 5.6 ± 3.2°, respectively; mean difference in calf circumference between the two sides was 0.9 ± 0.5 cm; and mean increase in Achilles tendon width versus the healthy side was 0.8 ± 0.2 cm. By 1 year post-surgery, there were no significant between-side differences in dorsiflexion and plantarflexion angle, or calf circumference. Conclusions Tendon-bundle surgery resulted in good ankle function restoration and low complication rates. Tendon-bundle surgery may reduce blood supply destruction and maximally preserve Achilles tendon length, and may be effective for treating Achilles tendon rupture with no defects.

  8. M1 and M2 macrophage recruitment during tendon regeneration induced by amniotic epithelial cell allotransplantation in ovine.

    Science.gov (United States)

    Mauro, Annunziata; Russo, Valentina; Di Marcantonio, Lisa; Berardinelli, Paolo; Martelli, Alessandra; Muttini, Aurelio; Mattioli, Mauro; Barboni, Barbara

    2016-04-01

    Recently, we have demonstrated that ovine amniotic epithelial cells (oAECs) allotransplanted into experimentally induced tendon lesions are able to stimulate tissue regeneration also by reducing leukocyte infiltration. Amongst leukocytes, macrophages (Mφ) M1 and M2 phenotype cells are known to mediate inflammatory and repairing processes, respectively. In this research it was investigated if, during tendon regeneration induced by AECs allotransplantation, M1Mφ and M2Mφ phenotype cells are recruited and differently distributed within the lesion site. Ovine AECs treated and untreated (Ctr) tendons were explanted at 7, 14, and 28 days and tissue microarchitecture was analyzed together with the distribution and quantification of leukocytes (CD45 positive), Mφ (CD68 pan positive), and M1Mφ (CD86, and IL12b) and M2Mφ (CD206, YM1 and IL10) phenotype related markers. In oAEC transplanted tendons CD45 and CD68 positive cells were always reduced in the lesion site. At day 14, oAEC treated tendons began to recover their microarchitecture, contextually a reduction of M1Mφ markers, mainly distributed close to oAECs, and an increase of M2Mφ markers was evidenced. CD206 positive cells were distributed near the regenerating areas. At day 28 oAECs treated tendons acquired a healthy-like structure with a reduction of M2Mφ. Differently, Ctr tendons maintained a disorganized morphology throughout the experimental time and constantly showed high values of M1Mφ markers. These findings indicate that M2Mφ recruitment could be correlated to tendon regeneration induced by oAECs allotransplantation. Moreover, these results demonstrate oAECs immunomodulatory role also in vivo and support novel insights into their allogeneic use underlying the resolution of tendon fibrosis. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Mechanical properties of the equine superficial digital flexor tendon relate to specific collagen cross-link levels.

    Science.gov (United States)

    Thorpe, C T; Stark, R J F; Goodship, A E; Birch, H L

    2010-11-01

    Damage to the flexor tendons, particularly the superficial digital flexor tendon (SDFT), is one of the most common musculoskeletal injuries sustained by horses competing in all disciplines. Our previous work has shown that SDFTs from different individuals show a wide variation in mechanical strengths; this is important clinically as it may relate to predisposition to injury. The high mechanical strength of tendon relies on the correct orientation of collagen molecules within fibrils and stabilisation by the formation of chemical cross-links between collagen molecules. It is not known whether the variation in SDFT mechanical properties between individuals relates to differences in collagen cross-link levels. Enzyme-derived, intermolecular cross-linking of tendon collagen correlates with mechanical properties of the SDFT. SDFTs were collected from 38 horses and mechanically tested to failure. Structural and material properties were calculated from the load/deformation plot and cross-sectional area for each tendon. Following mechanical testing, pyrrolic cross-link levels were measured using a spectrophotometric assay for Ehrlich's reactivity and pyridinoline levels were quantified by HPLC. Cross-link levels were correlated with mechanical properties and statistical significance tested using a Pearson's correlation test. Pyrrole cross-link levels showed a significant positive correlation with ultimate stress (P = 0.004), yield stress (P = 0.003) and elastic modulus (P = 0.018) of the tendons, despite being a minor cross-link in these tendons. There was no significant correlation of mechanical properties with either hydroxylysyl- or lysyl-pyridinoline levels. Given the low absolute levels of pyrrole, we suggest that the correlation with high mechanical strength is through an indirect mechanism. Understanding the nature of the relationships between pyrrole cross-links, other matrix characteristics and tendon material properties may allow development of strategies to

  10. Direct Repair of Chronic Achilles Tendon Ruptures Using Scar Tissue Located Between the Tendon Stumps.

    Science.gov (United States)

    Yasuda, Toshito; Shima, Hiroaki; Mori, Katsunori; Kizawa, Momoko; Neo, Masashi

    2016-07-20

    Several surgical procedures for chronically ruptured Achilles tendons have been reported. Resection of the interposed scar tissue located between the tendon stumps and reconstruction using normal autologous tissue have been well described. We developed a direct repair procedure that uses scar tissue, which obviates the need to use normal autologous tissue. Thirty consecutive patients with Achilles tendon ruptures with a delay in diagnosis of >4 weeks underwent removal of a section of scar and healing tissue with direct primary suture of the ends of the tendon without the use of allograft or autograft. Patients were followed for a mean time of 33 months. Preoperative and postoperative clinical outcomes were measured with the Achilles Tendon Total Rupture Score (ATRS) and the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score. In addition, the patients underwent preoperative and postoperative functional measurements and magnetic resonance imaging. Lastly, we evaluated the histology of the interposed healing tissue. The mean AOFAS scores were 82.8 points preoperatively and 98.1 points postoperatively. The mean postoperative ATRS was 92.0 points. At the time of the latest follow-up, none of the patients had experienced tendon reruptures or difficulties in walking or climbing stairs, and all except 2 patients could perform a single-limb heel rise. All athletes had returned to their pre-injury level of sports participation. Preoperative T2-weighted magnetic resonance imaging showed that 22 Achilles tendons were thickened with diffuse intratendinous high-signal alterations, and 8 Achilles tendons were thinned. Postoperative T2-weighted magnetic resonance imaging findings included fusiform-shaped tendon thickening and homogeneous low-signal alterations of the tendons in all patients. Histologically, the interposed scar tissue consisted of dense collagen fibers. Shortening of the tissue between the 2 tendon ends that included healing scar and direct

  11. Distal tendinosis of the tibialis anterior tendon.

    Science.gov (United States)

    Beischer, Andrew D; Beamond, Ben M; Jowett, Andrew J L; O'Sullivan, Richard

    2009-11-01

    Disorders of the tibialis anterior (TA) tendon have infrequently been reported but spontaneous rupture of this tendon is well recognized. The clinical presentation of tendinosis without rupture of the distal TA has not previously been reported and is the basis of this paper. A study of 29 patients diagnosed with distal TA tendinosis was undertaken. Data collected included, patient demographics, weight, height, pain profile and examination findings. All patients underwent MRI of the symptomatic foot. Operative findings of those patients undergoing surgery for this condition were collected. Twenty-nine patients (32 feet) were included in the study group. Their mean age was 62 years and 27 patients were female. Twenty-one patients were overweight. The usual presenting symptom was burning medial midfoot pain that was often reported to be worst at night. Swelling over the TA tendon was frequently observed. On MRI the TA was thickened in all patients. Longitudinal split tears were observed in 19 feet. Chondral thinning and/or osteophyte formation at the first tarsometatarsal or medial naviculocuneiform joints was observed in 11 feet. Eleven feet underwent surgery. Universally the TA tendon was macroscopically thickened and had lost its normal fibrillary appearance. Longitudinal split tears were observed in eight tendons. Pathology was typical of a degenerative tendinosis. Distal TA tendinosis is a condition that seems to predominantly affect overweight elderly women. It often presents with nocturnal burning medial midfoot pain.

  12. No Telescoping Effect with Dual Tendon Vibration.

    Directory of Open Access Journals (Sweden)

    Valeria Bellan

    Full Text Available The tendon vibration illusion has been extensively used to manipulate the perceived position of one's own body part. However, findings from previous research do not seem conclusive sregarding the perceptual effect of the concurrent stimulation of both agonist and antagonist tendons over one joint. On the basis of recent data, it has been suggested that this paired stimulation generates an inconsistent signal about the limb position, which leads to a perceived shrinkage of the limb. However, this interesting effect has never been replicated. The aim of the present study was to clarify the effect of a simultaneous and equal vibration of the biceps and triceps tendons on the perceived location of the hand. Experiment 1 replicated and extended the previous findings. We compared a dual tendon stimulation condition with single tendon stimulation conditions and with a control condition (no vibration on both 'upward-downward' and 'towards-away from the elbow' planes. Our results show a mislocalisation towards the elbow of the position of the vibrated arm during dual vibration, in line with previous results; however, this did not clarify whether the effect was due to arm representation contraction (i.e., a 'telescoping' effect. Therefore, in Experiment 2 we investigated explicitly and implicitly the perceived arm length during the same conditions. Our results clearly suggest that in all the vibration conditions there was a mislocalisation of the entire arm (including the elbow, but no evidence of a contraction of the perceived arm length.

  13. Animal Models for Tendon Repair Experiments: A Comparison of Pig, Sheep and Human Deep Flexor Tendons in Zone II.

    Science.gov (United States)

    Peltz, Tim Sebastian; Hoffman, Stuart William; Scougall, Peter James; Gianoutsos, Mark Peter; Savage, Robert; Oliver, Rema Antoinette; Walsh, William Robert

    2017-09-01

    This laboratory study compared pig, sheep and human deep flexor tendons in regards to their biomechanical comparability. To investigate the relevant biomechanical properties for tendon repair experiments, the tendons resistance to cheese-wiring (suture drag/splitting) was assessed. Cheese-wiring of a suture through a tendon is an essential factor for repair gapping and failure in a tendon repair. Biomechanical testing showed that forces required to pulling a uniform suture loop through sheep or pig tendons in Zone II were higher than in human tendons. At time point zero of testing these differences did not reach statistical significance, but differences became more pronounced when forces were measured beyond initial cheese-wiring (2 mm, 5 mm and 10 mm). The stronger resistance to cheese-wiring was more pronounced in the pig tendons. Also regarding size and histology, sheep tendons were more comparable to human tendons than pig tendons. Differences in tendon bio-properties should be kept in mind when comparing and interpreting the results of laboratory tendon experiments.

  14. Robot Arm with Tendon Connector Plate and Linear Actuator

    Science.gov (United States)

    Ihrke, Chris A. (Inventor); Diftler, Myron A. (Inventor); Bridgwater, Lyndon (Inventor); Nguyen, Vienny (Inventor); Millerman, Alexander (Inventor)

    2014-01-01

    A robotic system includes a tendon-driven end effector, a linear actuator, a flexible tendon, and a plate assembly. The linear actuator assembly has a servo motor and a drive mechanism, the latter of which translates linearly with respect to a drive axis of the servo motor in response to output torque from the servo motor. The tendon connects to the end effector and drive mechanism. The plate assembly is disposed between the linear actuator assembly and the tendon-driven end effector and includes first and second plates. The first plate has a first side that defines a boss with a center opening. The second plate defines an accurate through-slot having tendon guide channels. The first plate defines a through passage for the tendon between the center opening and a second side of the first plate. A looped end of the flexible tendon is received within the tendon guide channels.

  15. Sex Differences in Outcome After an Acute Achilles Tendon Rupture

    National Research Council Canada - National Science Library

    Grävare Silbernagel, Karin; Brorsson, Annelie; Olsson, Nicklas; Eriksson, Bengt I; Karlsson, Jon; Nilsson-Helander, Katarina

    2015-01-01

    Background: Tendon healing differs between the sexes. Comparisons in outcome between the sexes after an Achilles tendon rupture are often not possible because of the small cohort (<20%) of women. Purpose...

  16. 21 CFR 888.3025 - Passive tendon prosthesis.

    Science.gov (United States)

    2010-04-01

    ...) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3025 Passive tendon prosthesis. (a... flexor tendon of the hand. The device is implanted for a period of 2 to 6 months to aid growth of a new...

  17. Healing of AchiIIes Tendon lnjury : Ultrasonographic Findings

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Hyoen [Chungang University College of Medicine, Seoul (Korea, Republic of)

    1995-06-15

    To evaluate the ultrasonographic findings of ruptured Achilles tendon after healing by surgical or conservative treatment. Ultrasonography of Achilles tendon was performed in 15 patients with Achilles tendon injury that was believed to be cured after surgical or conservative treatment. We used 7MHz liner transducer. Ultrasonographic characteristics of the affected tendon were compared with those of the opposite healthy tendon in terms of echogenicity and thickness of tendon, contour disruption, and surrounding fluid collection. The thickness of the affected Achilles tendon was significantly greater than that of the healthy tendon(P<0.001). Ultrasonographic findings included focal hylpoechogenicity(4), diffusehypoechogenicity(9), isoecho-genicity(2) and focal sonolucent area(6). Ultrasonographic findings of healed Achilles are diffuse increase in thickness and diffuse or focal decrease in echogenicity in the avsence of surrounding fluid collection or hematoma

  18. Tenomodulin is Required for Tendon Endurance Running and Collagen I Fibril Adaptation to Mechanical Load

    Directory of Open Access Journals (Sweden)

    Sarah Dex

    2017-06-01

    Full Text Available Tendons are dense connective tissues that attach muscles to bone with an indispensable role in locomotion because of their intrinsic properties of storing and releasing muscle- generated elastic energy. Tenomodulin (Tnmd is a well-accepted gene marker for the mature tendon/ligament lineage and its loss-of -function in mice leads to a phenotype with distinct signs of premature aging on tissue and stem/progenitor cell levels. Based on these findings, we hypothesized that Tnmd might be an important factor in the functional performance of tendons. Firstly, we revealed that Tnmd is a mechanosensitive gene and that the C-terminus of the protein co-localize with collagen I-type fibers in the extracellular matrix. Secondly, using an endurance training protocol, we compared Tnmd knockout mice with wild types and showed that Tnmd deficiency leads to significantly inferior running performance that further worsens with training. In these mice, endurance running was hindered due to abnormal response of collagen I cross-linking and proteoglycan genes leading to an inadequate collagen I fiber thickness and elasticity. In sum, our study demonstrates that Tnmd is required for proper tendon tissue adaptation to endurance running and aids in better understanding of the structural-functional relationships of tendon tissues.

  19. The Puller-Follower Control of Compliant and Noncompliant Antagonistic Tendon Drives in Robotic Systems

    Directory of Open Access Journals (Sweden)

    Veljko Potkonjak

    2011-11-01

    Full Text Available This paper proposes a new control strategy for noncompliant and compliant antagonistic tendon drives. It is applied to a succession of increasingly complex single‐joint systems, starting with a linear and noncompliant system and ending with a revolute, nonlinearly tendon coupled and compliant system. The last configuration mimics the typical human joint structure, used as a model for certain joints of the anthropomimetic robot ECCEROBOT. The control strategy is based on a biologically inspired puller‐ follower concept, which distinguishes the roles of the agonist and antagonist motors. One actuator, the puller, is considered as being primarily responsible for the motion, while the follower prevents its tendon from becoming slack by maintaining its tendon force at some non‐zero level. Certain movements require switching actuator roles; adaptive co‐contraction is used to prevent tendons slackening, while maintaining energetic efficiency. The single‐joint control strategy is then evaluated in a multi‐ joint system. Dealing with the gravitational and dynamic effects arising from the coupling in a multi‐joint system, a robust control design has to be applied with on‐line gravity compensation. Finally, an experiment corresponding to object grasping is presented to show the controller

  20. The Puller-Follower Control of Compliant and Noncompliant Antagonistic Tendon Drives in Robotic Systems

    Directory of Open Access Journals (Sweden)

    Veljko Potkonjak

    2011-11-01

    Full Text Available This paper proposes a new control strategy for noncompliant and compliant antagonistic tendon drives. It is applied to a succession of increasingly complex single-joint systems, starting with a linear and noncompliant system and ending with a revolute, nonlinearly tendon coupled and compliant system. The last configuration mimics the typical human joint structure, used as a model for certain joints of the anthropomimetic robot ECCEROBOT. The control strategy is based on a biologically inspired puller-follower concept, which distinguishes the roles of the agonist and antagonist motors. One actuator, the puller, is considered as being primarily responsible for the motion, while the follower prevents its tendon from becoming slack by maintaining its tendon force at some non-zero level. Certain movements require switching actuator roles; adaptive co-contraction is used to prevent tendons slackening, while maintaining energetic efficiency. The single-joint control strategy is then evaluated in a multi-joint system. Dealing with the gravitational and dynamic effects arising from the coupling in a multi-joint system, a robust control design has to be applied with on-line gravity compensation. Finally, an experiment corresponding to object grasping is presented to show the controller's robustness to external disturbances.

  1. Morphometric analysis of growing tenocytes in the superficial digital flexor tendon of piglets.

    Science.gov (United States)

    Takahashi, Naoki; Tangkawattana, Prasarn; Ootomo, Yoshiki; Hirose, Takuya; Minaguchi, Jun; Ueda, Hiromi; Yamada, Michi; Takehana, Kazushige

    2017-12-22

    The fine structures of different tendons in various animals at different ages have been studied extensively to reveal their arrangement and growth patterns. However, knowledge of the microstructures of the growing tenocytes in the tendons of piglets is still lacking. Thus, we performed the first morphometric analysis to describe the characteristics of tenocytes in the metacarpal superficial digital flexor tendon of 0-, 10- and 20-day-old piglets. In the present study, hydrochloric acid/collagenase digestion was applied to remove the interstitial connective tissue to obtain clear visualization of intact tenocytes and their cytoplasmic processes (Cp). Then, the morphometry of the tenocytes was investigated by optical and electron microscopy. The mean ± SE values of the fascicle area, number of tenocytes/fascicle, cell density, number of Cp/tenocyte, length of Cp, and thickness of Cp were compared among the three age groups. Significant differences (judged at P<0.05) were found in almost all morphometric aspects among the age groups, except for the number of Cp/cell (P=0.545) and thickness of the Cp (P=0.105). A decrease of cell density corresponded with an increase in the length of the Cp, which were extended to connect either with the Cp of the other tenocytes or the surrounding endotendineum. Moreover, an increase of the fascicle area reflected the increase in tendon diameter. The revealed morphometric characteristics are thus the outcome of tendon growth.

  2. Tendon Mineralization Is Progressive and Associated with Deterioration of Tendon Biomechanical Properties, and Requires BMP-Smad Signaling in the Mouse Achilles Tendon Injury Model

    Science.gov (United States)

    Zhang, Kairui; Asai, Shuji; Hast, Michael W.; Liu, Min; Usami, Yu; Iwamoto, Masahiro; Soslowsky, Louis J.; Enomoto-Iwamoto, Motomi

    2016-01-01

    Ectopic tendon mineralization can develop following tendon rupture or trauma surgery. The pathogenesis of ectopic tendon mineralization and its clinical impact have not been fully elucidated yet. In this study, we utilized a mouse Achilles tendon injury model to determine whether ectopic tendon mineralization alters the biomechanical properties of the tendon and whether BMP signaling is involved in this condition. A complete transverse incision was made at the midpoint of the right Achilles tendon in 8-week-old CD1 mice and the gap was left open. Ectopic cartilaginous mass formation was found in the injured tendon by 4 weeks post-surgery and ectopic mineralization was detected at 8–10 weeks post-surgery. Ectopic mineralization grew over time and volume of the mineralized materials of 25-weeks samples was about 2.5 fold bigger than that of 10-weeks samples, indicating that injury-induced ectopic tendon mineralization is progressive. In vitro mechanical testing showed that max force, max stress and mid-substance modulus in the 25-weeks samples were significantly lower than the 10-weeks samples. We observed substantial increases in expression of bone morphogenetic protein family genes in injured tendons 1 week post-surgery. Immunohistochemical analysis showed that phosphorylation of both Smad1 and Smad3 were highly increased in injured tendons as early as 1 week post-injury and remained high in ectopic chondrogenic lesions 4 weeks post-injury. Treatment with the BMP receptor kinase inhibitor (LDN193189) significantly inhibited injury-induced tendon mineralization. These findings indicate that injury-induced ectopic tendon mineralization is progressive, involves BMP signaling and associated with deterioration of tendon biomechanical properties. PMID:26825318

  3. Comparison of the early period effects of bone marrow-derived mesenchymal stem cells and platelet-rich plasma on the Achilles tendon ruptures in rats.

    Science.gov (United States)

    Yuksel, Serdar; Guleç, M Akif; Gultekin, M Zeki; Adanır, Oktay; Caglar, Aysel; Beytemur, Ozan; Onur Küçükyıldırım, B; Avcı, Ali; Subaşı, Cansu; İnci, Çiğdem; Karaoz, Erdal

    2016-09-01

    This study aims to histopathologically, biomechanically, and immunohistochemically compare the fourth-week efficiencies of local platelet-rich plasma (PRP) and bone marrow-derived mesenchymal stem cell (rBM-MSC) treatments of the Achilles tendon ruptures created surgically in rats. The study included 35 12-month-old male Sprague Dawley rats, with an average weight of 400-500 g. Five rats were used as donors for MSC and PRP, and 30 rats were separated into MSC, PRP, and control groups (n = 10). The Achilles tendons of the rats were cut transversely, the MSC from bone marrow was administered to the MSC group, the PRP group received PRP, and the control group received physiological saline to create the same surgical effect. In previous studies, it was shown that this physiological saline does not have any effect on tendon recovery. Thirty days after the treatment, the rats were sacrificed and their Achilles tendons were examined histopathologically, immunohistochemically, and biomechanically. The use of rBM-MSC and PRP in the Achilles tendon ruptures when the tendon is in its weakest phase positively affected the recovery of the tendon in histopathologic, immunohistochemical, and biomechanical manners compared to the control group (p tendon recovery, such as IL2, VEGF, transforming growth factor-beta, and HGF, were significantly higher in the MSC group than those of the PRP and control groups (p tendon and increase its structural strength. The use of PRP and MSC provides hope for the treatment of the Achilles tendon ruptures that limit human beings' functionalities and quality of life, particularly for athletes. It is thought that the use of MSC can be more effective for tendon healing; hence, more extensive and advanced studies are needed on this topic.

  4. Compensatory muscle activation caused by tendon lengthening post Achilles tendon rupture

    Science.gov (United States)

    Suydam, Stephen M.; Buchanan, Thomas S.; Manal, Kurt; Silbernagel, Karin Gravare

    2013-01-01

    Purpose The purpose of this study was to establish a relationship between the lengthening of the Achilles tendon post rupture and surgical repair to muscle activation patterns during walking in order to serve as a reference for post-surgical assessment. Method The Achilles tendon lengths were collected from 4 patients with an Achilles tendon rupture 6 and 12 month post-surgery along with 5 healthy controls via ultrasound. EMG was collected from the triceps surae muscles and tibialis anterior during over-ground walking. Results Achilles lengths at 6 and 12 months post-surgery were significantly longer (p Achilles tendon rupture; no side to side difference was found in the healthy controls. The triceps surae muscles’ activations were fair to moderately correlated to the Achilles lengths (0.38 Achilles tendon length and iEMG from the triceps surae muscles indicate that loss of function is primarily caused by anatomical changes in the tendon and the appearance of muscle weakness is due to a lack of force transmission capability. This study indicates that when aiming for full return of function and strength an important treatment goal appears to be to minimize tendon elongation. Level of evidence Prognostic prospective case series. Level IV. PMID:23609529

  5. Acute partial rupture of the common extensor tendon

    OpenAIRE

    Kachrimanis, G.; Papadopoulou, O.

    2010-01-01

    Rupture of the common extensor tendon is the most common acute tendon injury of the elbow. The authors describe a case of a patient with a clinical history of tendinopathy caused by functional overload of the common extensor tendon, treated also with infiltrations of steroids, and subsequent partial rupture of the tendon during sport activity. The diagnosis was made clinically and at ultrasound (US) examination; US follow-up after some time showed the healing of the lesion. This case confirms...

  6. Calcaneal tendon: imaging findings; Tendao calcaneo: avaliacao por imagem

    Energy Technology Data Exchange (ETDEWEB)

    Montandon, Cristiano; Fonseca, Cristiano Rezio; Montandon Junior, Marcelo Eustaquio [Colegio Brasileiro de Radiologia e Diagnostico por Imagem, Sao Paulo, SP (Brazil)]. E-mail: crismontandon@hotmail.com; Lobo, Leonardo Valadares; Ribeiro, Flavia Aparecida de Souza; Teixeira, Kim-Ir-Sen Santos [Goias Univ., Goiania, GO (Brazil). Hospital de Clinicas. Dept. de Diagnostico por Imagem e Anatomia Patologica

    2003-12-01

    We reviewed the radiological and clinical features of 23 patients with calcaneal tendon diseases, who were submitted to ultrasound or magnetic resonance imaging. The objective of this study was to characterize the lesions for a precise diagnosis of calcaneal tendon injuries. A wide range of calcaneal tendon diseases include degenerative lesions, inflammation of the peritendinous tissue such as peritendinitis and bursitis, and rupture. Imaging methods are essential in the diagnosis, treatment and follow-up of calcaneal tendon diseases. (author)

  7. MRI in flexor tendon rupture after collagenase injection

    Energy Technology Data Exchange (ETDEWEB)

    Khurana, Shruti [Lady Hardinge Medical College, New Delhi (India); Wadhwa, Vibhor [University of Arkansas for Medical Sciences, Little Rock, AR (United States); Chhabra, Avneesh [UT Southwestern Medical Center, Dallas, TX (United States); Johns Hopkins University, Baltimore, MD (United States); Amirlak, Bardia [UT Southwestern Medical Center, Dallas, TX (United States)

    2017-02-15

    Flexor tendon rupture is an unusual complication following collagenase injection to relieve contractures. These patients require a close follow-up and in the event of tendon rupture, a decision has to be made whether to repair the tendon or manage the complication conservatively. The authors report the utility of MRI in the prognostication and management of a patient with Dupuytren's contracture, who underwent collagenase injection and subsequently developed flexor digitorum profundus tendon rupture. (orig.)

  8. Reinforced concrete T-beams externally prestressed with unbonded carbon fiber-reinforced polymer tendons

    DEFF Research Database (Denmark)

    Bennitz, Anders; Nilimaa, Jonny; Täljsten, Björn

    2012-01-01

    This study describes a series of experiments examining the behavior of seven beams prestressed with unbonded external carbon fiberreinforced polymer (CFRP) tendons anchored using a newly developed anchorage and post-tensioning system. The effects of varying the initial tendon depth, prestressing...... similar effects on the structural behavior of the strengthened beams; the minor differences that were observed are attributed to the difference between the modulus of elasticity of the CFRP and the steel used in the tests. The models predicted the beams' load-bearing behavior accurately but were less...

  9. Genipin crosslinking elevates the strength of electrochemically aligned collagen to the level of tendons.

    Science.gov (United States)

    Alfredo Uquillas, Jorge; Kishore, Vipuil; Akkus, Ozan

    2012-11-01

    Collagen-based tissue mimics are important in clinical research because collagen is the main structural element in tendons. The current study aimed to improve the mechanical strength of Electronically Aligned Collagen (ELAC) threads by optimizing several crosslinking parameters. The results indicated that elevating the concentration of genipin to 2% and the solvent to 90% ethanol significantly enhanced the wet ultimate tensile stress of ELAC threads to 109 MPa with a crosslinking degree of 65%. Furthermore, significantly higher adhesion and proliferation of hMSCs was observed in ELAC threads crosslinked with 2% genipin in 90% ethanol compared to 0.625% genipin in 1X PBS. In conclusion, ELAC threads with mechanical strength on par with native tendon have significant potential to be used as scaffolds in tendon tissue engineering applications. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Snapping popliteus tendon within an osteochondritis dissecans lesion: an unusual case of lateral knee pain.

    Science.gov (United States)

    Shukla, Dave R; Levy, Bruce A; Kuzma, Scott A; Stuart, Michael J

    2014-09-01

    The popliteus muscle is an important structure in the posterior knee, coursing from the distal lateral femoral condyle to the posterior tibia, and it initiates knee flexion, protects the lateral meniscus, and resists tibial external rotation. Abnormalities in the lateral femoral condyle may result in impaired tracking of the popliteus tendon over the lateral femoral condyle, causing pain and a snapping sensation. We report a case of a snapping popliteus tendon caused by an osteochondral defect of the lateral femoral condyle. We obtained a thorough medical history, performed a detailed physical examination, and performed diagnostic ultrasonography to accurately diagnose the condition. The patient underwent open popliteus tenotomy and tibial tenodesis with excellent results and full return to activity. Any abnormality of the lateral femoral condyle may predispose patients to snapping popliteus tendon and we believe early diagnosis utilizing ultrasonography imaging and surgical intervention may benefit these patients significantly.

  11. Motion Compensation of Tendon-Sheath Driven Continuum Manipulator for Endoscopic Surgery

    Directory of Open Access Journals (Sweden)

    Lau K. C.

    2015-01-01

    Full Text Available Tendon-sheath actuation mechanism is widely used in surgical robot, especially in endoscopic surgery, due to its capable of providing remote force and action transmission through long and flexible channel. However, hysteresis, backlash, nonlinear friction are the drawbacks of this mechanism. Our surgical robot use continuum manipulator which is useful in endoscopic surgery, due to its flexible and simple structure. Unlike other literatures that focus on tendon-sheath compensation only, the continuum manipulator is also taken into application level analysis. A model based feedforward motion compensation for tendon-sheath driven continuum manipulator is presented. The model is validated by using optical tracking system to trace the distal end position. Experiment result shows that the proposed model reduces the position error less than 5%.

  12. Development of high shrinkage polyethylene terephthalate (PET) shape memory polymer tendons for concrete crack closure

    Science.gov (United States)

    Teall, Oliver; Pilegis, Martins; Sweeney, John; Gough, Tim; Thompson, Glen; Jefferson, Anthony; Lark, Robert; Gardner, Diane

    2017-04-01

    The shrinkage force exerted by restrained shape memory polymers (SMPs) can potentially be used to close cracks in structural concrete. This paper describes the physical processing and experimental work undertaken to develop high shrinkage die-drawn polyethylene terephthalate (PET) SMP tendons for use within a crack closure system. The extrusion and die-drawing procedure used to manufacture a series of PET tendon samples is described. The results from a set of restrained shrinkage tests, undertaken at differing activation temperatures, are also presented along with the mechanical properties of the most promising samples. The stress developed within the tendons is found to be related to the activation temperature, the cross-sectional area and to the draw rate used during manufacture. Comparisons with commercially-available PET strip samples used in previous research are made, demonstrating an increase in restrained shrinkage stress by a factor of two for manufactured PET filament samples.

  13. Subscapularis tendon avulsions and biceps tendon dislocations. A series of forty five patients; Lesions isolees du tendon subscapularis et malpositions internes du tendon long biceps

    Energy Technology Data Exchange (ETDEWEB)

    Bernageau, J. [Hopital Lariboisiere, 75 - Paris (France); Goutallier, D. [Hopital Henri-Mondor, 94 - Creteil (France)

    1997-12-01

    Our series consists of 45 lesions of the subscapularis tendon investigated by arthrography and CT arthrography. Arthrography demonstrated opacification of the sub-acromial bursa in 24 % of cases, internal malposition of the long head of biceps in 46 % of cases and direct signs of a lesion of the subscapularis tendon in 91 % of cases. CT arthrography showed incomplete transverse avulsion in 18 % of cases and complete transverse avulsion in 82 % of cases. The biceps was dislocated in 35 % of cases, and subluxated in 11 % of cases. The subscapularis muscle was infiltrated by fat in 46 % of cases. Isolated lesions of the subscapularis can be difficult to diagnose clinically and are more frequent than generally thought. CT arthrography must therefore be requested at the slightest doubt, as the intraoperative search for a lesion of the subscapularis tendon is sometimes difficult. (authors)

  14. Lateral force transmission between human tendon fascicles

    DEFF Research Database (Denmark)

    Haraldsson, Bjarki T; Aagaard, Per; Qvortrup, Klaus

    2008-01-01

    Whether adjacent collagen fascicles transmit force in parallel is unknown. The purpose of the present study was to examine the magnitude of lateral force transmission between adjacent collagen fascicles from the human patellar and Achilles tendon. From each sample two adjacent strands of fascicles...... was transversally cut while the other fascicle and the fascicular membrane were kept intact. Cycle 3: both fascicles were cut in opposite ends while the fascicular membrane was left intact. A decline in peak force of 45% and 55% from cycle 1 to cycle 2, and 93% and 92% from cycle 2 to cycle 3 was observed...... in the patellar and Achilles tendon fascicles, respectively. A decline in stiffness of 39% and 60% from cycle 1 to cycle 2, and of 93% and 100% from cycle 2 to cycle 3 was observed in the patellar and Achilles tendon fascicles, respectively. The present data demonstrate that lateral force transmission between...

  15. Achilles tendon rupture; assessment of nonoperative treatment

    DEFF Research Database (Denmark)

    Barfod, Kristoffer Weisskirchner

    2014-01-01

    to be clarified, particularly the role of weight-bearing during early rehabilitation. Also, there is a need for a clinically applicable and accurate measurement to detect patients in risk of developing Achilles tendon elongation. PURPOSE: The aim of this PhD thesis was to evaluate non-operative treatment of acute......BACKGROUND: Acute Achilles tendon rupture is a frequent and potentially disabling injury. Over the past decade a change in treatment of acute Achilles tendon rupture away from operative towards non-operative treatment has taken place. However, the optimal non-operative treatment protocol remains.......3 mm), inter-rater reliability (ICC 0.97, SEM 3.3 mm and MDC 9.3 mm) and validity (measurement error 2%). CONCLUSION: Treatment algorithms across Scandinavia showed considerable variation, though operative treatment and controlled early weight-bearing was the preferred treatment in Denmark, Norway...

  16. PERONEAL TENDON LESIONS IN ATHLETES (REVIEW

    Directory of Open Access Journals (Sweden)

    E. E. Achkasov

    2016-01-01

    Full Text Available The authors analyzed scientific literature in respect of various issues in treatment of athletes with peroneal muscles lesions starting from 1987 till 2016. Key search and publications selection was made in PubMed and russian national electronic scientific library eLIBRARY. Peroneal tendons pathology is not the major but the underestimated cause of pain in lateral and hindfoot as well as of foot dysfunction which is difficult to distinguish from lesions of lateral ligaments of the ankle joint. Untreated lesions of peroneal tendons can result in chronic ankle pain and significant functional disorders. The purpose of the present paper is to improve the current comprehension of anatomy, to identify factors contributing to pathology, to perform diagnostic evaluation of peroneal tendons and to review current treatment options of such lesions.

  17. Triple Achilles Tendon Rupture: Case Report.

    Science.gov (United States)

    Saxena, Amol; Hofer, Deann

    2017-11-16

    We present a case report with 1-year follow-up data of a 57-year-old male soccer referee who had sustained an acute triple Achilles tendon rupture injury during a game. His triple Achilles tendon rupture consisted of a rupture of the proximal watershed region, a rupture of the main body (mid-watershed area), and an avulsion-type rupture of insertional calcific tendinosis. The patient was treated surgically with primary repair of the tendon, including tenodesis with anchors. Postoperative treatment included non-weightbearing for 4 weeks and protected weightbearing until 10 weeks postoperative, followed by formal physical therapy, which incorporated an "antigravity" treadmill. The patient was able to return to full activity after 26 weeks, including running and refereeing, without limitations. Copyright © 2017 The American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  18. A Simulation Model for Extensor Tendon Repair

    Directory of Open Access Journals (Sweden)

    Elizabeth Aronstam

    2017-07-01

    Full Text Available Audience: This simulation model is designed for use by emergency medicine residents. Although we have instituted this at the PGY-2 level of our residency curriculum, it is appropriate for any level of emergency medicine residency training. It might also be adapted for use for a variety of other learners, such as practicing emergency physicians, orthopedic surgery residents, or hand surgery trainees. Introduction: Tendon injuries commonly present to the emergency department, so it is essential that emergency physicians be competent in evaluating such injuries. Indeed, extensor tendon repair is included as an ACGME Emergency Medicine Milestone (Milestone 13, Wound Management, Level 5 – “Performs advanced wound repairs, such as tendon repairs…”.1 However, emergency medicine residents may have limited opportunity to develop these skills due to a lack of patients, competition from other trainees, or preexisting referral patterns. Simulation may provide an alternative means to effectively teach these skills in such settings. Previously described tendon repair simulation models that were designed for surgical trainees have used rubber worms4, licorice5, feeding tubes, catheters6,7, drinking straws8, microfoam tape9, sheep forelimbs10 and cadavers.11 These models all suffer a variety of limitations, including high cost, lack of ready availability, or lack of realism. Objectives: We sought to develop an extensor tendon repair simulation model for emergency medicine residents, designed to meet ACGME Emergency Medicine Milestone 13, Level 5. We wished this model to be simple, inexpensive, and realistic. Methods: The learner responsible content/educational handout component of our innovation teaches residents about emergency department extensor tendon repair, and includes: 1 relevant anatomy 2 indications and contraindications for emergency department extensor tendon repair 3 physical exam findings 4 tendon suture techniques and 5 aftercare. During

  19. Primary flexor tendon repair: surgical techniques based on the anatomy and biology of the flexor tendon system.

    Science.gov (United States)

    Tonkin, M A

    1991-01-01

    The anatomy, biology and bio-mechanics of the flexor tendon system demand a precise approach to flexor tendon repair. Within the fibroosseous canal, the synovial fluid and a complex intratendinous vascular network provide nutrition for intrinsic flexor tendon healing. Retention of the synovial sheath theoretically maintains an enclosed tendon/tendon sheat environment in which the tendon repair is bathed in synovial fluid, and may glide within a smooth tunnel. The preservation of the intricate double tendon inter-relationship and the annular pulley system is vital to the efficiency of finger flexion. This review details surgical and postoperative techniques aimed at restoring the normal anatomy and providing optimal conditions for the return of flexor tendon function.

  20. Ultrasound of the elbow with emphasis on detailed assessment of ligaments, tendons, and nerves

    Energy Technology Data Exchange (ETDEWEB)

    De Maeseneer, Michel, E-mail: Michel.demaeseneer@uzbrussel.be [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium); Brigido, Monica Kalume, E-mail: Mbrigido@med.umich.edu [Department of Radiology, University of Michigan, Ann Arbor, MI (United States); Antic, Marijana, E-mail: Misscroa@gmail.com [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium); Lenchik, Leon, E-mail: Llenchik@wakehealth.edu [Department of Radiology, Wake Forest University, Winston-Salem, NC (United States); Milants, Annemieke, E-mail: Annemieke.Milants@gmail.com [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium); Vereecke, Evie, E-mail: Evie.Vereecke@kuleuven-kulak.be [Department of Anatomy, KULAK, Katholieke Universiteit Leuven, Campus Kortrijk, Kortrijk (Belgium); Jager, Tjeerd [Aalsters Stedelijk Ziekenhuis, Aalst (Belgium); Shahabpour, Maryam, E-mail: Maryam.Shahabpour@uzbrussel.be [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium)

    2015-04-15

    Highlights: •Medial and lateral tendons: the different muscles forming these tendons can be followed up to the insertion. The imaging anatomy is reviewed. •Medial and lateral ligaments: the anatomy is complex and specialized imaging planes and arm positions are necessary for accurate assessment. •Biceps tendon: the anatomy of the distal biceps and lacertus fibrosus are discussed and illustrated with cadaveric correlation. •US imaging of the nerves about the elbow and visualization of the possible compression points is discussed. -- Abstract: The high resolution and dynamic capability of ultrasound make it an excellent tool for assessment of superficial structures. The ligaments, tendons, and nerves about the elbow can be fully evaluated with ultrasound. The medial collateral ligament consists of an anterior and posterior band that can easily be identified. The lateral ligament complex consists of the radial collateral ligament, ulnar insertion of the annular ligament, and lateral ulnar collateral ligament, easily identified with specialized probe positioning. The lateral ulnar collateral ligament can best be seen in the cobra position. On ultrasound medial elbow tendons can be followed nearly up to their common insertion. The pronator teres, flexor carpi radialis, palmaris longus, and flexor digitorum superficialis can be identified. The laterally located brachioradialis and extensor carpi radialis longus insert on the supracondylar ridge. The other lateral tendons can be followed up to their common insertion on the lateral epicondyle. The extensor digitorum, extensor carpi radialis brevis, extensor digiti minimi, and extensor carpi ulnaris can be differentiated. The distal biceps tendon is commonly bifid. For a complete assessment of the distal biceps tendon specialized views are necessary. These include an anterior axial approach, medial and lateral approach, and cobra position. In the cubital tunnel the ulnar nerve is covered by the ligament of Osborne

  1. MicroRNA29a Treatment Improves Early Tendon Injury.

    Science.gov (United States)

    Watts, Ashlee E; Millar, Neal L; Platt, Josh; Kitson, Susan M; Akbar, Moeed; Rech, Raquel; Griffin, Jay; Pool, Roy; Hughes, Tom; McInnes, Iain B; Gilchrist, Derek S

    2017-10-04

    Tendon injuries (tendinopathies) are common in human and equine athletes and characterized by dysregulated collagen matrix, resulting in tendon damage. We have previously demonstrated a functional role for microRNA29a (miR29a) as a post-transcriptional regulator of collagen 3 expression in murine and human tendon injury. Given the translational potential, we designed a randomized, blinded trial to evaluate the potential of a miR29a replacement therapy as a therapeutic option to treat tendinopathy in an equine model that closely mimics human disease. Tendon injury was induced in the superficial digital flexor tendon (SDFT) of 17 horses. Tendon lesions were treated 1 week later with an intralesional injection of miR29a or placebo. miR29a treatment reduced collagen 3 transcript levels at week 2, with no significant changes in collagen 1. The relative lesion cross-sectional area was significantly lower in miR29a tendons compared to control tendons. Histology scores were significantly better for miR29a-treated tendons compared to control tendons. These data support the mechanism of microRNA-mediated modulation of early pathophysiologic events that facilitate tissue remodeling in the tendon after injury and provides a strong proof of principle that a locally delivered miR29a therapy improves early tendon healing. Copyright © 2017 The American Society of Gene and Cell Therapy. All rights reserved.

  2. Management of open achilles tendon injury: Primary repair and ...

    African Journals Online (AJOL)

    Background: Achilles tendon injuries have progressive increase worldwide in the last few decades. This is attributable to increase in both competitive and recreational sports. In most of the literature written on Achilles tendon injuries there were rarely any information about open Achilles tendon lacerations. In fact, Achilles ...

  3. Bilateral spontaneous rupture of flexor digitorum profundus tendons.

    LENUS (Irish Health Repository)

    O'Sullivan, S T

    2012-02-03

    Spontaneous tendon rupture is an unusual condition usually associated with underlying disease processes such as rheumatoid arthritis, chronic renal failure or bony abnormalities of the hand. We report a case of spontaneous, non-concurrent bilateral rupture of flexor profundus tendons in an otherwise healthy individual. Treatment was successful and consisted of a two-stage reconstruction of the ruptured tendon.

  4. Measurement of tendon reflexes by surface electromyography in normal subjects

    NARCIS (Netherlands)

    Stam, J.; van Crevel, H.

    1989-01-01

    A simple method for measuring the tendon reflexes was developed. A manually operated, electronic reflex hammer was applied that enabled measurement of the strength of tendon taps. Reflex responses were recorded by surface electromyography. Stimulus-response relations and latencies of tendon reflexes

  5. Semitendinosus Tendon for Solitary Use in Anterior Cruciate ...

    African Journals Online (AJOL)

    for reconstruction of the anterior cruciate ligament requires adequate tendon length (>28 cm) and four strand construct diameter (>8 mm). This study sought to determine the dimensions of the semitendinosus tendon graft among Kenyans. Methods: Forty pairs of ST tendons were harvested from formalin fixed cadavers by ...

  6. Region-specific mechanical properties of the human patella tendon

    DEFF Research Database (Denmark)

    Haraldsson, B T; Aagaard, P; Krogsgaard, M

    2004-01-01

    The present study investigated the mechanical properties of tendon fascicles from the anterior and posterior human patellar tendon. Collagen fascicles from the anterior and posterior human patellar tendon in healthy young men (mean +/- SD, 29.0 +/- 4.6 yr, n = 6) were tested in a mechanical rig. ...

  7. Painful Snapping Hip Owing to Bifid Iliopsoas Tendon and ...

    African Journals Online (AJOL)

    A case of internal snapping hip owing to a bifid iliopsoas tendon is described with a concurrent labral tear in a young active female. The labral tear was identified on magnetic resonance imaging, and the snapping bifid tendon on dynamic ultrasound. The patient was administered bupivicaine and steroid around the tendon ...

  8. Posterior tibial tendon dysfunction by bone imprisonment | Zejjari ...

    African Journals Online (AJOL)

    The radiological assessment finds imprisonment of posterior tibial tendon in the internal retromalleolar bony canal. The patient received a release of the tendon with resection of the bony canal in full. The posterior tibial tendon showed longitudinal laceration was sutured and the internal retromalleolar canal was closed.

  9. Ultrasound diagnostics of muscle and tendon injuries

    Directory of Open Access Journals (Sweden)

    Stević Ruža

    2009-01-01

    Full Text Available Introduction. Sonography is a useful technique for the investigation of a number of musculoskeletal disorders. The most common indication for ultrasonography of muscles and tendons is the diagnosis of traumatic lesions, distinguishing them from other disorders and follow-up of healing process. Objective. The purpose of this paper is to show the importance of ultrasound in the diagnosis of muscle and tendon injuries. Methods. The study included 170 patients (148 male and 22 female, mean age 29.6 years (range 14-60 years. All examinations were performed by linear transducer of 7.5-10 MHz, with longitudinal and transverse scanning. Ultrasound examination followed physical examination. Results. Traumatic lesions of muscles were diagnosed in 113 patients (66.7% and tendon injuries in 57 cases (33.2%. The muscle changes detected by ultrasonography were the following: 70 (61.9% partial and two (1.76% complete ruptures, 22 (19.46% haematoma, 9 (7.96% strains grade I, 4 fibroses and 4 ossifying myositis 4 (3.5%, respectively. Complications of muscle injuries were diagnosed in two cases, a muscular hernia and an arteriovenous fistula. Among tendon injuries, 21 (33.8% ruptures and 36 (66.1% tendinitis were diagnosed. Accompanying effusion in the bursa of patients with tendon injuries was found in 9 cases. Conclusion. Ultrasonography allowed visualization and objective assessment of the type and the extent of traumatic pathomorphological changes of muscles and tendons. Such diagnostic possibilities of ultrasonography are especially important in the choice of appropriate therapy.

  10. Biomechanical and histological evaluations of the doubled semitendinosus tendon autograft after anterior cruciate ligament reconstruction in sheep.

    Science.gov (United States)

    Kondo, Eiji; Yasuda, Kazunori; Katsura, Taro; Hayashi, Riku; Kotani, Yoshihisa; Tohyama, Harukazu

    2012-02-01

    A sheep or goat anterior cruciate ligament (ACL) reconstruction model with the semitendinosus tendon autograft has not as of yet been established. The semitendinosus tendon graft may be necrotized after ACL reconstruction until 12 weeks. Structural properties of the femur-graft-tibia complex may not be restored to the normal ACL level even at 12 months after surgery. Controlled laboratory study. Thirty-eight mature sheep were used. In each animal, the right knee underwent ACL reconstruction using the semitendinosus tendon autograft. Two of them were not tested because of pneumonia. Twenty of 36 sheep were used for biomechanical evaluations. Five randomly selected animals were sacrificed at 0, 12, 24, or 52 weeks after surgery. In each animal, both the knees were harvested, and the left knee was used to obtain the control data. The remaining 16 sheep were used for histological evaluation. Two or 3 randomly selected animals were sacrificed at 0, 2, 6, 12, 24, or 52 weeks after surgery. The tendon graft was predominantly acellular at 2 weeks. Although cell infiltration increased at 6 weeks, the core portion remained necrotic even at 12 weeks. At 24 and 52 weeks, the necrotic lesion disappeared in the core portion. In each period, the anteroposterior translation of the reconstructed knee remained significantly greater than that of the control (P tendon autograft until 12 weeks. Although the structural properties of the femur-graft-tibia complex gradually improved, they were not completely restored to the femur-ACL-tibia complex level even at 52 weeks. Remodeling of the semitendinosus tendon autograft after ACL reconstruction is not different from that of the bone-tendon-bone graft. This study has suggested that vigorous activity should not be permitted for patients in the early periods after ACL reconstruction using semitendinosus tendon autografts, which are necrotized and weakened after surgery.

  11. Spontaneous Achilles tendon rupture in alkaptonuria

    Science.gov (United States)

    Alajoulin, Omar A.; Alsbou, Mohammed S.; Ja’afreh, Somayya O.; Kalbouneh, Heba M.

    2015-01-01

    Alkaptonuria (AKU) is a rare inborn metabolic disease characterized by accumulation of homogentisic acid (HGA). Excretion of HGA in urine causes darkening of urine and its deposition in connective tissues causes dark pigmentation (ochronosis), early degeneration of articular cartilage, weakening of the tendons, and subsequent rupture. In this case report, we present a rare case of a patient presented with unilateral spontaneous rupture of Achilles tendon due to AKU. The patient developed most of the orthopedic manifestations of the disease earlier than typical presentations. Alkaptonuria patients should avoid strenuous exercises and foot straining especially in patients developing early orthopedic manifestations. PMID:26620992

  12. [Comprehensive treatment in Achilles tendon rupture].

    Science.gov (United States)

    Matus-Jiménez, Juan; Avalos, Cecilia Henríquez

    2007-01-01

    Due to incapacity caused by calcaneal tendon injuries for the reintegration of patients back to their daily activities and/or sparts it is necessary to decrease the time of reinstatement of patients. At present these times have improved by a good surgical technique and an early rehabilitation, and the patient is returned quickly as he sees less disability. It is proposed in this paper a type of surgical treatment and an early rehabilitation program, which have shortened the time of disability and incorporation to their daily activities and sports to eight weeks in 10 patients with Achilles tendon plasty.

  13. Differences in tendon properties in elite badminton players with or without patellar tendinopathy

    DEFF Research Database (Denmark)

    Couppé, C; Kongsgaard, M; Aagaard, P

    2012-01-01

    The aim of this study was to examine the structural and mechanical properties of the patellar tendon in elite male badminton players with and without patellar tendinopathy. Seven players with unilateral patellar tendinopathy (PT group) on the lead extremity (used for forward lunge) and nine players...

  14. Effects of replacing soybean meal with chickpea seeds in the diet on mechanical and thermal properties of tendon tissue in broiler chicken.

    Science.gov (United States)

    Muszynski, S; Kwiecien, M; Swietlicki, M; Dobrowolski, P; Tatarczak, J; Gladyszewska, B

    2018-02-01

    The efficiency of the musculoskeletal system of broiler chickens, in particular during locomotion and in ensuring its supportive function, depends directly on the adequate function and mechanical endurance of soft tissues, including tendons. However, little is known whether the properties of musculoskeletal soft tissues can be influenced by changes of dietary protein. We substituted soybean meal with raw chickpea seeds as the primary protein source in the diet and studied the effects it had on the mechanical and thermal properties of drumstick tendons in broiler Ross 308 chickens. In the experiment, 160 chicks were divided into 2 groups, receiving in their diet either soybean meal (n = 80) or chickpea seeds (n = 80). The experiment lasted 42 days. The physical condition of the drumstick tendons was analyzed on the basis of a tensile test and the results of thermal denaturation as measured by a differential scanning calorimetry. The mechanical evaluation of tendon tensile strength of the broilers fed with chickpea seeds demonstrated an increase in the ultimate strain (for over 22%, P tendon until rupture (for over 57%, P tendon collagen cross-linking as transition onset temperature decreased (from 63.8 to 61.8°C, P tendons and showed that thermal analysis can be a useful tool for studying the effect of nutrition on the development and structural changes in tendons of broiler chickens. © 2017 Poultry Science Association Inc.

  15. Chiasma crurale: intersection of the tibialis posterior and flexor digitorum longus tendons above the ankle. Magnetic resonance imaging-anatomic correlation in cadavers

    Energy Technology Data Exchange (ETDEWEB)

    Buck, Florian M. [VA San Diego Medical Center, Department of Radiology, San Diego, CA (United States); Institut fuer Diagnostische Radiologie, Zurich (Switzerland); Gheno, Ramon; Nico, Marcelo A.C.; Trudell, Debra J.; Resnick, Donald [VA San Diego Medical Center, Department of Radiology, San Diego, CA (United States); Haghighi, Parviz [VA San Diego Medical Center, Department of Pathology, San Diego, CA (United States)

    2010-06-15

    To determine the precise anatomy and magnetic resonance (MR) imaging appearance of the chiasma crurale in cadavers, paying special attention to degenerative changes Twelve fresh human ankles were harvested from 11 nonembalmed cadavers (mean age at death 77 years) and used according to institutional guidelines. MR imaging and MR tenography were used to investigate the anatomy of the chiasma crurale using proton density-weighted sequences. The gross anatomy of the chiasma crurale was evaluated and compared to the MR imaging findings. Histology was used to elucidate further the structure of the chiasma crurale. Above the chiasma, five specimens had a small amount of fat tissue between the tibialis posterior and flexor digitorum longus tendon. In all specimens both tendons had a sheath below the chiasma but not above it. At the central portion of the chiasma there was no soft tissue between the tendons, except in two specimens that showed an anatomic variant consisting of a thick septum connecting the tibial periosteum and the deep transverse fascia of the leg. In MR images, eight specimens showed what were believed to be degenerative changes in the tendons at the level of the chiasma. However, during gross inspection and histologic analysis of the specimens, there was no tendon degeneration visible. At the central portion of the chiasma, there is no tissue between the tibialis posterior and flexor digitorum longus tendons unless there is an anatomic variant. At the chiasma crurale, areas with irregular tendon surfaces are normal findings and are not associated with tendon degeneration (fraying). (orig.)

  16. Lubricin in human achilles tendon: The evidence of intratendinous sliding motion and shear force in achilles tendon.

    Science.gov (United States)

    Sun, Yu-Long; Wei, Zhuang; Zhao, Chunfeng; Jay, Gregory D; Schmid, Thomas M; Amadio, Peter C; An, Kai-Nan

    2015-06-01

    Achilles tendon is one of the most commonly injured tendons. Mechanical force is regarded as a major causative factor. However, the biomechanics of Achilles tendon and mechanical mechanism of the injuries are unclear. Lubricin expresses at regions exposed to sliding motion and shear force in a number of tissues. This study investigated the distribution and concentration of lubricin in human Achilles tendons for better understanding the biomechanics of Achilles tendon. Achilles tendons were harvested from nine cadavers. Lubricin was extracted from various locations proximal to the calcaneal insertion and quantified with ELISA. The distribution of lubricin was investigated with immunohistochemistry. Lubricin was mainly identified at the interfaces of tendon fascicles, especially in the mid-portion of the tendon. The concentration of lubricin in Achilles tendons varied by individual and the distance from its calcaneal insertion. The distal portion of the tendon had a higher concentration of lubricin than the proximal regions of the tendon. This study suggests the presence of intratendinous sliding motion of fascicles and shear force at interfaces of fascicles in human Achilles tendon. Shear force could be an important mechanical factor for the development of Achilles tendinopathy and rupture. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  17. Histologic pattern of biomechanic properties of the carbon fiber-augmented ligament tendon. A laboratory and clinical study.

    Science.gov (United States)

    Mendes, D G; Iusim, M; Angel, D; Rotem, A; Roffman, M; Grishkan, A; Mordohohovich, D; Boss, J

    1985-06-01

    Implantation of carbon fiber tow (CFT) for ligament and tendon augmentation was investigated in ten dogs and 45 patients. CFT produced a new structure with a remarkably consistent structural pattern. The basic pattern of the CFT-augmented unit consisted of a core of carbon fiber surround by concentric layers of fibroblasts and collagen fibers. This unit structure was developed from continuous irritation of physical structure of the carbon fiber. In dogs, ultimate tensile strength of the augmented tendon one year after surgery averaged 88% of natural tendon. Digestion of the connective tissue component of the CFT unit exposed the original carbon fiber tow. The connective tissue-free CFT maintained its original tensile strength. The continuous production of collagenous tissue surrounding carbon fibers produced a ligamentous structure that was physiologically compatible and biomechanically sufficient.

  18. A Rare Case of Simultaneous Acute Bilateral Quadriceps Tendon Rupture and Unilateral Achilles Tendon Rupture.

    Science.gov (United States)

    Leong, Wei Yee; Gheorghiu, Daniel; Rao, Janardhan

    2013-01-01

    There have been multiple reported cases of bilateral quadriceps tendon ruptures (QTR) in the literature. These injuries frequently associated with delayed diagnosis, which results in delayed surgical treatment. In very unusual cases, bilateral QTRs can be associated with other simultaneous tendon ruptures. We present a rare case of bilateral QTR with a simultaneous Achilles Tendon Rupture involving a 31 years old Caucasian man who is a semi-professional body builder taking anabolic steroids. To date bilateral QTR with additional TA rupture has only been reported once in the literature and to our knowledge this is the first reported case of bilateral QTR and simultaneous TA rupture in a young, fit and healthy individual. The diagnosis of bilateral QTR alone can sometimes be challenging and the possibility of even further tendon injuries should be carefully assessed. A delay in diagnosis could result in delay in treatment and potentially worse outcome for the patient.

  19. Human Achilles tendon glycation and function in diabetes

    DEFF Research Database (Denmark)

    Couppé, Christian; Svensson, Rene Brüggebusch; Madsen, Mads Kongsgaard

    2016-01-01

    Diabetic patients have an increased risk of foot ulcers, and glycation of collagen may increase tissue stiffness. We hypothesized that the level of glycemic control (glycation) may affect Achilles tendon stiffness, which can influence gait pattern. We therefore investigated the relationship between...... collagen glycation, Achilles tendon stiffness parameters and plantar pressure in poorly (n = 22) and well (n = 22) controlled diabetic patients, including healthy age matched (45-70 yrs) controls (n = 11). There were no differences in any of outcome parameters (collagen cross-linking or tendon stiffness...... concentrations (55%, P Achilles tendon material stiffness was higher in DB (54%, P Achilles tendon material stiffness and skin connective...

  20. Development of the human Achilles tendon enthesis organ

    Science.gov (United States)

    Shaw, H M; Vázquez, Osorio T; McGonagle, D; Bydder, G; Santer, R M; Benjamin, M

    2008-01-01

    The attachment of the Achilles tendon is part of an ‘enthesis organ’ that reduces stress concentration at the hard–soft tissue interface. The organ also includes opposing sesamoid and periosteal fibrocartilages, a bursa and Kager's fat pad. In addition, the deep crural and plantar fasciae contribute to Achilles stress dissipation and could also be regarded as components. Here we describe the sequence in which these various tissues differentiate. Serial sections of feet from spontaneously aborted foetuses (crown rump lengths 22–322 mm) were examined. All slides formed part of an existing collection of histologically sectioned embryological material, obtained under Spanish law and housed in the Universidad Complutense, Madrid. From the earliest stages, it was evident that the Achilles tendon and plantar fascia had a mutual attachment to the calcaneal perichondrium. The first components of the enthesis organ to appear (in the 45-mm foetus) were the retrocalcaneal bursa and the crural fascia. The former developed by cavitation within the mesenchyme that later gave rise to Kager's fat pad. The tip of the putative fat pad protruded into the developing bursa in the 110-mm foetus and fully differentiated adipocytes were apparent in the 17-mm foetus. All three fibrocartilages were first recognisable in the 332-mm foetus – at which time adipogenesis had commenced in the heel fat pad. The sequence in which the various elements became apparent suggests that bursal formation and the appearance of the crural fascia may be necessary to facilitate the foot movements that subsequently lead to fibrocartilage differentiation. The later commencement of adipogenesis in the heel than in Kager's pad probably reflects the non-weight environment in utero. The direct continuity between plantar fascia and Achilles tendon that is characteristic of the adult reflects the initial attachment of both structures to the calcaneal perichondrium rather than to the skeletal anlagen itself

  1. Debridement and Functional Rehabilitation for Achilles Tendon Infection Following Tendon Repair.

    Science.gov (United States)

    Bae, Seung Hwan; Lee, Ho-Seong; Seo, Sang Gyo; Kim, Sang Woo; Gwak, Heui-Chul; Bae, Su-Young

    2016-07-20

    An infected Achilles tendon after tendon repair is particularly difficult to treat because of the poor vascularity of the tendon as well as the thin surrounding soft tissue. For treatment of an infected Achilles tendon following tendon repair, we first focused on complete debridement and then promoted fibrous scar healing of the Achilles tendon using functional treatment. We retrospectively reviewed all of the medical records of 15 tertiary referral patients with postoperative infection of the Achilles tendon occurring between 2007 and 2012. The mean follow-up time was 33 months (range, 22 to 97 months). The infected tissue and the necrotic tendon were debrided, and the ankle was placed in a short leg splint for 2 weeks. The splint was then replaced with an ankle brace for the next 4 weeks. Partial weight-bearing was allowed immediately, and full weight-bearing was allowed at 2 weeks postoperatively. We assessed and recorded the physical parameters such as the range of motion, calf circumference, ability to perform a single-limb heel rise, patient satisfaction, and Arner-Lindholm scale. Laboratory tests, postoperative ultrasonography, and isokinetic plantar flexion power tests were also performed. At a mean time of 17 days (range, 8 to 30 days) after debridement, infection signs such as discharge from the wound, redness, and local warmth resolved. The wound had healed and the stitches were removed at a mean of 17 days following the wound repair. At the time of the latest follow-up, there were no signs of active infection. Achilles tendon continuity recovered in all patients by fibrous scar healing. Compared with the contralateral side, there was no difference in the ankle range of motion in 8 patients. According to the Arner-Lindholm scale, 9 of the 15 results were excellent and 6 were good. Ten patients were able to perform a single-limb heel rise. Eleven of 15 patients returned to their pre-injury recreational activities. Diffuse homogeneous echotexture of the

  2. Achilles Tendon Rupture: Avoiding Tendon Lengthening during Surgical Repair and Rehabilitation

    Science.gov (United States)

    Maquirriain, Javier

    2011-01-01

    Achilles tendon rupture is a serious injury for which the best treatment is still controversial. Its primary goal should be to restore normal length and tension, thus obtaining an optimal function. Tendon elongation correlates significantly with clinical outcome; lengthening is an important cause of morbidity and may produce permanent functional impairment. In this article, we review all factors that may influence the repair, including the type of surgical technique, suture material, and rehabilitation program, among many others. PMID:21966048

  3. The Effect of Sodium Hyaluronate on Ligamentation and Biomechanical Property of Tendon in Repair of Achilles Tendon Defect with Polyethylene Terephthalate Artificial Ligament: A Rabbit Tendon Repair Model.

    Science.gov (United States)

    Li, Shengkun; Ma, Kui; Li, Hong; Jiang, Jia; Chen, Shiyi

    2016-01-01

    The Achilles tendon is the most common ruptured tendon of human body. Reconstruction with polyethylene terephthalate (PET) artificial ligament is recommended in some serious cases. Sodium hyaluronate (HA) is beneficial for the healing of tendon injuries. We aimed to determine the effect of sodium hyaluronate in repair of Achilles tendon defect with PET artificial ligament in an animal tendon repair model. Sixteen New Zealand White rabbits were divided into two groups. Eight rabbits repaired with PET were assigned to PET group; the other eight rabbits repaired with PET along with injection of HE were assigned to HA-PET group. All rabbits were sacrificed at 4 and 8 weeks postoperatively for biomechanical and histological examination. The HA-PET group revealed higher biomechanical property compared with the PET group. Histologically, more collagen tissues grew into the HA-PET group compared with PET group. In conclusion, application of sodium hyaluronate can improve the healing of Achilles tendon reconstruction with polyethylene terephthalate artificial ligament.

  4. A Rare Case of Simultaneous Acute Bilateral Quadriceps Tendon Rupture and Unilateral Achilles Tendon Rupture

    Directory of Open Access Journals (Sweden)

    Wei Yee Leong

    2013-07-01

    Full Text Available Introduction: There have been multiple reported cases of bilateral quadriceps tendon ruptures (QTR in the literature. These injuries frequently associated with delayed diagnosis, which results in delayed surgical treatment. In very unusual cases, bilateral QTRs can be associated with other simultaneous tendon ruptures. Case Report: We present a rare case of bilateral QTR with a simultaneous Achilles Tendon Rupture involving a 31 years old Caucasian man who is a semi-professional body builder taking anabolic steroids. To date bilateral QTR with additional TA rupture has only been reported once in the literature and to our knowledge this is the first reported case of bilateral QTR and simultaneous TA rupture in a young, fit and healthy individual. Conclusion: The diagnosis of bilateral QTR alone can sometimes be challenging and the possibility of even further tendon injuries should be carefully assessed. A delay in diagnosis could result in delay in treatment and potentially worse outcome for the patient. Keywords: Quadriceps tendon rupture; Achilles tendon rupture; Bilateral.

  5. The "turtleneck" pulley plasty for finger flexor tendon repair.

    Science.gov (United States)

    Goubier, Jean-Noel; Lafosse, Thibault; Teboul, Frédéric

    2014-03-01

    Injuries to the flexor tendons are frequent. Even when correctly treated, they can cause a loss of mobility of the digits secondary to postoperative adhesions. Further, conflicts between the tendon suture and the pulleys can limit the range of motion of the tendon and the flexion of the fingers. We propose a new pulley plasty that permits immediate retraining and avoids conflict with the tendon suture. Ten patients underwent surgery for a tendon injury in zone II, with no lesions of the associated pedicles. The tendons were repaired by a 4-strand stitch technique associated with a continuous peritendinous suture. Pulley plasty was systematically performed on A2, A4, or both. Eight patients recovered a satisfactory range of motion with a finger to palm distance of pulleys was necessary. This plasty technique is simple to carry out, reliable, and reproducible. Because it facilitates tendon repair and reinforces the existing pulleys, it permits immediate retraining and controlled active mobilization.

  6. A posterior tibial tendon skipping rope

    NARCIS (Netherlands)

    van Sterkenburg, M. N.; Haverkamp, D.; van Dijk, C. N.; Kerkhoffs, G. M. M. J.

    2010-01-01

    This report presents an athletic patient with swelling and progressive pain on the posteromedial side of his right ankle on weight bearing. MRI demonstrated tenosynovitis and suspicion of a length rupture. On posterior tibial tendoscopy, there was no rupture, but medial from the tendon a tissue cord

  7. Engaging Stem Cells for Customized Tendon Regeneration

    Directory of Open Access Journals (Sweden)

    Hatim Thaker

    2012-01-01

    Full Text Available The need for a consistent therapeutic approach to tendon injury repair is long overdue. Patients with tendon microtears or full ruptures are eligible for a wide range of invasive and non invasive interventions, often subjectively decided by the physician. Surgery produces the best outcomes, and while studies have been conducted to optimize graft constructs and to track outcomes, the data from these studies have been inconclusive on the whole. What has been established is a clear understanding of healthy tendon architecture and the inherent process of healing. With this knowledge, tissue regeneration efforts have achieved immense progress in scaffold design, cell line selection, and, more recently, the appropriate use of cytokines and growth factors. This paper evaluates the plasticity of bone-marrow-derived stem cells and the elasticity of recently developed biomaterials towards tendon regeneration efforts. Mesenchymal stem cells (MSCs, hematopoietic progenitor cells, and poly(1,8-octanediol co-citrate scaffolds (POC are discussed in the context of established grafting strategies. With POC scaffolds to cradle the growth of MSCs and hematopoietic progenitor cells, developing a fibroelastic network guided by cytokines and growth factors may contribute towards consistent graft constructs, enhanced functionality, and better patient outcomes.

  8. Can Shockwave Therapy Improve Tendon Metabolism?

    NARCIS (Netherlands)

    Zwerver, Johannes; Waugh, Charlotte; van der Worp, Henk; Scott, Alex; Ackermann, PW; Hart, DA

    2016-01-01

    Shockwave treatments are commonly used in the management of tendon injuries and there is increasing evidence for its clinical effectiveness. There is a paucity of fundamental (in vivo) studies investigating the biological action of shockwave therapy. Destruction of calcifications, pain relief and

  9. Achilles Tendon Repair, A Modified Technique

    Directory of Open Access Journals (Sweden)

    Sohrab Keyhani

    2013-12-01

    Full Text Available   Background: Wound complications following open repair for acute Achilles tendon ruptures (AATR remain the subject of significant debate. The aim of this study is to investigate the effects of covering repaired AATR using well-nourished connective tissues (paratenon and deep fascia to avoid complications after open repair.   Methods: In this case series study, open repair was performed for 32 active young patients with AATR. After the tendon was repaired, the deep fascia and paratenon was used to cover the Achilles tendon. Patients were followed for two years and any wound complication was recorded. During the last visit, the American Orthopedic Foot and Ankle Society (AOFAS ankle-hind foot score was completed for all patients. Calf circumference and ankle range of motion were measured and compared with the contralateral side. Patients were asked about returning to previous sports activities and limitations with footwear. Results: Only, one patient developed deep wound infection (3%. None of the patients had any discomfort around the operation area, limitation with footwear, sural nerve injury, re-rupture, and skin adhesion. The AOFAS score averaged 92.5±6. Two patients (7% were unable to return to previous sports activities because of moderate pain in heavy physical exercises. The calf circumference and ankle ROM were similar between healthy and operated sides. Conclusion: The present study showed that fascial envelope for full covering of the repaired Achilles tendon may help to prevent the occurrence of wound complications.

  10. Test-retest reliability of echo intensity parameters in healthy Achilles tendons using a semi-automatic tracing procedure.

    Science.gov (United States)

    Schneebeli, Alessandro; Del Grande, Filippo; Vincenzo, Gabriele; Cescon, Corrado; Barbero, Marco

    2017-11-01

    To evaluate the test-retest reliability of the ultrasound echo intensity parameters on healthy Achilles tendon using a semi-automatic tracing procedure. Eighteen healthy volunteers participated. B-mode images were acquired in the transverse plane (mid-tendon; insertion) and used to analyze tendon echogenicity. Grayscale distribution of the pixels within the selected ROIs was represented as a histogram. Descriptive statistics of the grayscale distribution (mean, variance, skewness, kurtosis, and entropy) and parameters from the co-occurrence matrix (contrast, energy, and homogeneity) were calculated. Reliability of echo intensity parameters of the mid-Achilles tendon ranged from high to very high with an ICC 2.k of 0.94 for echogenicity, 0.87 for variance, 0.80 for skewness, 0.72 for kurtosis, 0.89 for entropy, 0.90 for contrast, 0.91 for energy, and 0.93 for homogeneity, while for tendon insertion they ranged from moderate to high with an ICC 2.k of 0.74 for echogenicity, 0.88 for variance, 0.75 for skewness, 0.55 for kurtosis, 0.87 for entropy, 0.70 for contrast, 0.77 for energy, and 0.56 for homogeneity. Ultrasound echo intensity is a reliable technique to characterize the internal structure of the Achilles tendon.

  11. A new strain energy function for modelling ligaments and tendons whose fascicles have a helical arrangement of fibrils.

    Science.gov (United States)

    Shearer, Tom

    2015-09-18

    A new strain energy function for the hyperelastic modelling of ligaments and tendons whose fascicles have a helical arrangement of fibrils is derived. The stress-strain response of a single fascicle whose fibrils exhibit varying levels of crimp throughout its radius is calculated and used to determine the form of the strain energy function. The new constitutive law is used to model uniaxial extension test data for human patellar tendon and is shown to provide an excellent fit, with the average relative error being 9.8%. It is then used to model shear and predicts that the stresses required to shear a tendon are much smaller than those required to uniaxially stretch it to the same strain level. Finally, the strain energy function is used to model ligaments and tendons whose fascicles are helical, and the relative effects of the fibril helix angle, the fascicle helix angle and the fibril crimp variable are compared. It is shown that they all have a significant effect; the fibril crimp variable governs the non-linearity of the stress-strain curve, whereas the helix angles primarily affect its stiffness. Smaller values of the helix angles lead to stiffer tendons; therefore, the model predicts that one would expect to see fewer helical sub-structures in stiff positional tendons, and more in those that are required to be more flexible. Copyright © 2015 The Author. Published by Elsevier Ltd.. All rights reserved.

  12. Metrenperone enhances collagen turnover and remodeling in the early stages of healing of tendon injury in rabbit.

    Science.gov (United States)

    Oryan, Ahmad; Silver, Ian A; Goodship, Allen E

    2010-12-01

    This study evaluated the effects of metrenperone on healing of unilateral, collagenase-induced lesions in the Superficial Digital Flexor Tendons (SDFT) of rabbits. After controlled injury of the left SDFT, nine rabbits received daily treatment with metrenperone for 28 days. Another nine were untreated controls; in both groups the contra-lateral tendons served as uninjured controls. Histological and ultrastructural changes, mechanical properties, dry weight, collagen content, and amount of DNA in healing and control tendons were assessed 28 days after injury. Restoration of structural hierarchy was more organized in treated than in untreated tendons while cellularity was greater in the latter. At the ultrastructural level, collagen in treated lesions was predominantly in the form of small-diameter, new fibrils, with few large, old fibrils; in untreated lesions there was a high proportion of large, old fibrils but relatively few small, new ones. The amount of DNA in untreated injuries was much greater than in normal tendons, while in treated lesions it was not significantly different from that of uninjured controls. There were no significant differences in total collagen, stiffness and ultimate strength of injured, treated, and untreated tendons 28 days after injury. Both were significantly weaker than their corresponding contralaterals. The findings suggest that metrenperone had positive effects on collagen turnover, remodelling, and organization during acute inflammation and fibroplasia. Provided that the new fibrils subsequently matured in a normal manner, mechanical characteristics of the organized scar should be better than those of an untreated lesion.

  13. Changes in histoanatomical distribution of types I, III and V collagen promote adaptative remodeling in posterior tibial tendon rupture

    Directory of Open Access Journals (Sweden)

    Érika Satomi

    2008-01-01

    Full Text Available INTRODUCTION: Posterior tibial tendon dysfunction is a common cause of adult flat foot deformity, and its etiology is unknown. PURPOSE: In this study, we characterized the morphologic pattern and distribution of types I, III and V collagen in posterior tibial tendon dysfunction. METHOD: Tendon samples from patients with and without posterior tibial tendon dysfunction were stained by immunofluorescence using antibodies against types I, III and V collagen. RESULTS: Control samples showed that type V deposited near the vessels only, while surgically obtained specimens displayed type V collagen surrounding other types of collagen fibers in thicker adventitial layers. Type III collagen levels were also increased in pathological specimens. On the other hand, amounts of collagen type I, which represents 95% of the total collagen amount in normal tendon, were decreased in pathological specimens. CONCLUSION: Fibrillogenesis in posterior tibial tendon dysfunction is altered due to higher expression of types III and V collagen and a decreased amount of collagen type I, which renders the originating fibrils structurally less resistant to mechanical forces.

  14. High-resolution MRI assessment of dactylitis in psoriatic arthritis shows flexor tendon pulley and sheath-related enthesitis.

    Science.gov (United States)

    Tan, Ai Lyn; Fukuba, Eiji; Halliday, Nicola Ann; Tanner, Steven F; Emery, Paul; McGonagle, Dennis

    2015-01-01

    Dactylitis is a hallmark of psoriatic arthritis (PsA) where flexor tenosynovitis is common. This study explored the microanatomical basis of dactylitis using high-resolution MRI (hrMRI) to visualise the small entheses around the digits. Twelve patients with psoriatic dactylitis (4 fingers, 8 toes), and 10 healthy volunteers (6 fingers, 4 toes) had hrMRI of the digits using a 'microscopy' coil and contrast enhancement. All structures were evaluated including the tendons and ligaments, related enthesis organs, pulleys, volar/plantar plates and tendon sheaths. In dactylitis, collateral ligament enthesitis was seen in nine digits (75%), extensor tendon enthesitis in six digits (50%), functional enthesitis (5 digits, 42%), abnormal enhancement at the volar plates (2/5 joints, 40%) and the plantar plate (1/5 joints, 20%). Nine cases (75%) demonstrated flexor tenosynovitis, with flexor tendon pulley/flexor sheath microenthesopathy observed in 50% of all cases. Less abnormalities which were milder was observed in the normal controls, none of whom had any signal changes in the tendon pulleys or fibrous sheaths. This study provides proof of concept for a link between dactylitis and 'digital polyenthesitis' including disease of the miniature enthesis pulleys of the flexor tendons, further affirming the concept of enthesitis in PsA. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  15. Contribution of glycosaminoglycans to the microstructural integrity of fibrillar and fiber crimps in tendons and ligaments.

    Science.gov (United States)

    Franchi, Marco; De Pasquale, Viviana; Martini, Désirée; Quaranta, Marilisa; Macciocca, Maria; Dionisi, Alessio; Ottani, Vittoria

    2010-10-01

    The biomechanical roles of both tendons and ligaments are fulfilled by the extracellular matrix of these tissues. In particular, tension is mainly transmitted and resisted by protein (collagen, elastin) fibers, whereas compression is opposed by water-soluble glycosaminoglycans (GAGs). GAGs spanning the interfibrillar spaces and interacting with fibrils through the interfibrillar proteoglycans also seem to play a part in transmitting and resisting tensile stresses. Both tendons and ligaments showing similar composition, but different functional roles and collagen array, exhibit periodic undulations of collagen fibers or crimps. Each crimp is composed of many knots of each single fibril or fibrillar crimps. Fibrillar and fiber crimps play a mechanical role in absorbing the initial loading during elongation of both tendons and ligaments, and in recoiling fibrils and fibers when tissues have to return to their original length. This study investigated whether GAGs covalently attached to proteoglycan core proteins directly affect the 3D microstructural integrity of fibrillar crimp regions and fiber crimps in both tendons and ligaments. Achilles tendons and medial collateral ligaments of the knee from eight female Sprague-Dawley rats (90 days old) incubated in a chondroitinase ABC solution to remove GAGs were observed under a scanning electron microscope (SEM). In addition, isolated fibrils of these tissues obtained by mechanical disruption were analyzed by a transmission electron microscope (TEM). Both Achilles tendons and medial collateral ligaments of the rats after chemical or mechanical removal of GAGs still showed crimps and fibrillar crimps comparable to tissues with a normal GAG content. All fibrils in the fibrillar crimp region always twisted leftwards, thus changing their running plane, and then sharply bent, changing their course on a new plane. These data suggest that GAGs do not affect structural integrity or fibrillar crimp functions that seem mainly related

  16. Engineered stem cell niche matrices for rotator cuff tendon regenerative engineering.

    Science.gov (United States)

    Peach, M Sean; Ramos, Daisy M; James, Roshan; Morozowich, Nicole L; Mazzocca, Augustus D; Doty, Steven B; Allcock, Harry R; Kumbar, Sangamesh G; Laurencin, Cato T

    2017-01-01

    Rotator cuff (RC) tears represent a large proportion of musculoskeletal injuries attended to at the clinic and thereby make RC repair surgeries one of the most widely performed musculoskeletal procedures. Despite the high incidence rate of RC tears, operative treatments have provided minimal functional gains and suffer from high re-tear rates. The hypocellular nature of tendon tissue poses a limited capacity for regeneration. In recent years, great strides have been made in the area of tendonogenesis and differentiation towards tendon cells due to a greater understanding of the tendon stem cell niche, development of advanced materials, improved scaffold fabrication techniques, and delineation of the phenotype development process. Though in vitro models for tendonogenesis have shown promising results, in vivo models have been less successful. The present work investigates structured matrices mimicking the tendon microenvironment as cell delivery vehicles in a rat RC tear model. RC injuries augmented with a matrix delivering rat mesenchymal stem cells (rMSCs) showed enhanced regeneration over suture repair alone or repair with augmentation, at 6 and 12-weeks post-surgery. The local delivery of rMSCs led to increased mechanical properties and improved tissue morphology. We hypothesize that the mesenchymal stem cells function to modulate the local immune and bioactivity environment through autocrine/paracrine and/or cell homing mechanisms. This study provides evidence for improved tendon healing with biomimetic matrices and delivered MSCs with the potential for translation to larger, clinical animal models. The enhanced regenerative healing response with stem cell delivering biomimetic matrices may represent a new treatment paradigm for massive RC tendon tears.

  17. A longitudinal assessment of running economy and tendon properties in long-distance runners.

    Science.gov (United States)

    Kubo, Keitaro; Tabata, Tomonori; Ikebukuro, Toshihiro; Igarashi, Katsumi; Tsunoda, Naoya

    2010-07-01

    The aim of this study was to investigate longitudinal changes in tendon properties and running economy of long-distance runners (LDRs) in the preparatory periods of track season (TS) and road season (RS). Eleven well-trained LDRs and 6 untrained subjects participated in the present study. In each period, muscle strength, neural activation level, and tendon elongation for both knee extensors and plantar flexors, jump performances, and oxygen consumption during submaximal running velocities were measured. No significant differences observed in any measured variables between the 2 seasons for untrained subjects. For LDRs, the total running distance during 1 month preceding RS (832 +/- 95 km) was significantly longer than that during 1 month preceding TS (718 +/- 80 km). No significant differences in the muscle strength, neural activation level, and jump performances were found between TS and RS. The stiffness of tendon structures in RS was significantly lower than those in TS for both knee extensors (-14.4%, p = 0.023) and plantar flexors (-16.6%, p = 0.040). At 3 running velocities, the oxygen consumptions in RS were significantly lower than those in TS. These results suggested that the lower oxygen consumption during submaximal running velocities observed in the preparatory period of RS may be attributable to the more compliant tendon structures but not in the neuromuscular characteristics.

  18. Effect of tendon tensioning: an in vitro study in porcine extensor tendons.

    Science.gov (United States)

    Figueroa, David; Calvo, Rafael; Vaisman, Alex; Meleán, Patricio; Figueroa, Francisco

    2010-06-01

    Graft tensioning is a controversial issue in anterior cruciate ligament reconstruction (ACLR) that has not achieved consensus between peers. The purpose of this study is to determine if after tensioning tendon length and resistance to maximal load changes. We performed an in vitro study with 50 porcine extensors tendons. The first group (P=25) was tensioned with 80 N (19.97 lb) for 10 min, using an ACL graft preparation board. The second group (C=25) was used as control and was not tensioned. The average initial (groups P and C) and post tensioning tendon length (group C) were measured; the average initial and post tensioning tendon diameter were measured as well. All samples were fixated in a tube-clamp system connected to a tension sensor. The samples were stressed with continuous and progressive tension until ultimate failure at maximum load (UFML) occurs. The initial mean length was: P before tensioning=13.4 mm+/-1.4 mm (range 10.5-16.5); P after tensioning=13.8 mm+/-1.4 mm (range 11.5-16.5); C=13 mm+/-1.35 mm (p=0.005). The mean diameter was: P=5.6 mm (4.5-6); C=5.5 mm (range 4.5-6) (p>0.05). The UFML was: P=189.7 N (114-336); C=229.9 N (143-365) (p=0.029). Tendon tensioning with 80 N for 10 min produced 3% average elongation. These could be beneficial in ACLR since tendon tensioning decreases elongation of the graft after fixation. Regardless, tendon tensioning is not innocuous since it diminishes their resistance when continuously stressed until complete failure occurs.

  19. Chronic Achilles Tendon Rupture Reconstructed With Achilles Tendon Allograft and Xenograft Combination.

    Science.gov (United States)

    Hollawell, Shane; Baione, William

    2015-01-01

    More than 20% of acute Achilles tendon injuries are misdiagnosed, leading to chronic or neglected ruptures. Some controversy exists regarding how to best manage an acute Achilles tendon rupture. However, a general consensus has been reached that chronic rupture with ≥3 cm of separation is associated with functional morbidity and, therefore, should be managed operatively. It has been demonstrated that the functional outcomes of surgically treated Achilles ruptures are superior to the nonoperative outcomes in a chronic setting. In the present report, we reviewed 4 patients with chronic Achilles tendon ruptures that were successfully treated with an Achilles tendon interposition allograft and simultaneous augmentation with a xenograft. The median duration of rupture was 11 (range 8 to 16) weeks, the median gap between the proximal and distal segments of the tendon was 4.75 (range 3.5 to 6) cm, and the patients were able to return pain-free to all preinjury activities at a median of 14.5 (range 13.8 to 15.5) weeks, without the need for tendon transfer, lengthening, or additional intervention. The median duration of follow up was 37.25 (range 15.25 to 51.5) months, at which point the mean Foot and Ankle Outcomes Instrument core scale score was 97 ± 1 (mean normative score 53 ± 1), and the Foot and Ankle Outcomes Instrument shoe comfort core scale score was 100 ± 0 (mean normative score 59 ± 0). The combined Achilles allograft plus xenograft augmentation technique appears to be a reasonable option for the surgical treatment of chronic Achilles tendon rupture. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  20. Decellularized and Engineered Tendons as Biological Substitutes: A Critical Review

    Directory of Open Access Journals (Sweden)

    Arianna B. Lovati

    2016-01-01

    Full Text Available Tendon ruptures are a great burden in clinics. Finding a proper graft material as a substitute for tendon repair is one of the main challenges in orthopaedics, for which the requirement of a biological scaffold would be different for each clinical application. Among biological scaffolds, the use of decellularized tendon-derived matrix increasingly represents an interesting approach to treat tendon ruptures. We analyzed in vitro and in vivo studies focused on the development of efficient protocols for the decellularization and for the cell reseeding of the tendon matrix to obtain medical devices for tendon substitution. Our review considered also the proper tendon source and preclinical animal models with the aim of entering into clinical trials. The results highlight a wide panorama in terms of allogenic or xenogeneic tendon sources, specimen dimensions, physical or chemical decellularization techniques, and the cell type variety for reseeding from terminally differentiated to undifferentiated mesenchymal stem cells and their static or dynamic culture employed to generate implantable constructs tested in different animal models. We try to identify the most efficient approach to achieve an optimal biological scaffold for biomechanics and intrinsic properties, resembling the native tendon and being applicable in clinics in the near future, with particular attention to the Achilles tendon substitution.

  1. Shear Wave Measurements for Evaluation of Tendon Diseases.

    Science.gov (United States)

    Yeh, Chia-Lun; Kuo, Po-Ling; Gennisson, Jean-Luc; Brum, Javier; Tanter, Mickael; Li, Pai-Chi

    2016-11-01

    This paper investigated the feasibility of using supersonic shear wave measurements to quantitatively differentiate normal and damaged tendons based on their mechanical properties. Five freshly harvested porcine tendons excised from pig legs were used. Tendon damage was induced by incubating the tendons with a 1% w/v collagenase solution. Values of shear modulus were derived both by a time-of-flight (TOF) approach and a transverse isotropic plate model (TI-model). The results show that as the preload applied to the tendon increased from 0 to 3 N, the mean shear modulus derived based on the TOF approach, the TI-model, and Young's modulus estimated from mechanical testing increased from 14.6 to 89.9 kPa, 53.9 to 348 kPa, and from 1.45 to 10.36 MPa, respectively, in untreated tendons, and from 8.4 to 67 kPa, 28 to 258 kPa, and from 0.93 to 7.2 MPa in collagenase-treated tendons. Both the TOF approach and the TI-model correlated well with the changes in Young's modulus. Although there is bias on the estimation of shear modulus using the TOF approach, it still provides statistical significance to differentiate normal and damaged tendons. Our data indicate that supersonic shear wave imaging is a valuable imaging technique to assess tendon stiffness dynamics and characterize normal and collagenase-damaged tendons.

  2. Acute effects of constant torque and constant angle stretching on the muscle and tendon tissue properties.

    Science.gov (United States)

    Konrad, Andreas; Budini, Francesco; Tilp, Markus

    2017-08-01

    Static stretching induces acute structural changes of the muscle-tendon unit (MTU) that are related to the intensity or duration of stretching. It has been reported that stretching with a constant torque (CT) leads to greater joint range of motion changes than stretching with a constant angle (CA). Whether or not this difference is due to different structural changes of the MTUs of the lower leg and ankle plantar flexors is not known. Therefore, the purpose of this study was to compare the acute effects of single CA and CT stretching on various muscle and tendon mechanical properties. Seventeen young, healthy volunteers were tested on two separate days using either CT or CA stretching (4 × 30 s each). Before and after stretching, dorsiflexion range of motion (RoM), passive resistive torque (PRT), and maximum voluntary contraction (MVC) were measured with a dynamometer. Ultrasonography of the medial gastrocnemius (GM) muscle-tendon junction (MTJ) displacement allowed us to determine the length changes in the tendon and muscle, respectively, and hence to calculate their stiffness. Maximum dorsiflexion increased while PRT, muscle-tendon stiffness, and muscle stiffness decreased following both CA and CT stretching. There was a greater increase in RoM following CT stretching compared to CA stretching. Moreover, the decline in PRT was greater during CT stretching compared to CA stretching. As expected, several functional adaptations (RoM, PRT) were different between CT and CA stretching due to the higher intensity of CT stretching. However, no structural differences in the adaptations to the stretching modalities could be detected. We suggest that the different functional adaptations between CA and CT stretching are the consequence of different adaptations in the perception of stretch and pain.

  3. Can chronic stretching change the muscle-tendon mechanical properties? A review.

    Science.gov (United States)

    Freitas, S R; Mendes, B; Le Sant, G; Andrade, R J; Nordez, A; Milanovic, Z

    2017-08-12

    It is recognized that stretching is an effective method to chronically increase the joint range of motion. However, the effects of stretching training on the muscle-tendon structural properties remain unclear. This systematic review with meta-analysis aimed to determine whether chronic stretching alter the muscle-tendon structural properties. Published papers regarding longitudinal stretching (static, dynamic and/or PNF) intervention (either randomized or not) in humans of any age and health status, with more than 2 weeks in duration and at least 2 sessions per week, were searched in PubMed, PEDro, ScienceDirect and ResearchGate databases. Structural or mechanical variables from joint (maximal tolerated passive torque or resistance to stretch) or muscle-tendon unit (muscle architecture, stiffness, extensibility, shear modulus, volume, thickness, cross-sectional area, and slack length) were extracted from those papers. A total of 26 studies were selected, with a duration ranging from 3 to 8 weeks, and an average total time under stretching of 1165 seconds per week. Small effects were seen for maximal tolerated passive torque, but trivial effects were seen for joint resistance to stretch, muscle architecture, muscle stiffness, and tendon stiffness. A large heterogeneity was seen for most of the variables. Stretching interventions with 3- to 8-week duration do not seem to change either the muscle or the tendon properties, although it increases the extensibility and tolerance to a greater tensile force. Adaptations to chronic stretching protocols shorter than 8 weeks seem to mostly occur at a sensory level. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. [MR imaging of the Achilles tendon: evaluation of criteria for the differentiation of asymptomatic and symptomatic tendons].

    Science.gov (United States)

    Weber, C; Wedegärtner, U; Maas, L C; Buchert, R; Adam, G; Maas, R

    2011-07-01

    The purpose of this study was to develop quantitative and qualitative MRI criteria to differentiate between healthy and pathological Achilles tendons. 364 Achilles tendons were examined on a 1.5 T MRI scanner. 264 patients had Achilles tendon complaints, 100 asymptomatic Achilles tendons served as a control. T 1-weighted, T 2-weighted and a STIR sequence were performed in sagittal and axial orientation. Images were evaluated in consensus by two radiologists. Quantitative and qualitative criteria were assessed. A Mann-Whitney-U-Test and a regression analysis were used for statistical analysis. There were statistically significant differences between the patients with disorders and the control group concerning the depth (12.0 mm and 6.3 mm, p tendon, the area of the tendon cross section (1.60 mm (2) and 061 mm (2), p tendon depth (A4), length of bursa (A5) and area of tendon (F). The measurement of the Achilles tendon and the binary-logistic regression analysis allow differentiation between normal and pathological Achilles tendons. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Proximal tendon-prosthesis junction for active tendon implants of the hand: a biomechanical comparison of 2 techniques.

    Science.gov (United States)

    Thompson, Matthew J; Owen, John R; McDowell, Charles L; Wayne, Jennifer S

    2015-01-01

    To study the biomechanical characteristics (percent stretch, stiffness, and ultimate load) of 2 tendon-prosthesis techniques used to connect the proximal tendon stump to silicone active tendon implants used in reconstruction of flexor tendons. We evaluated percent stretch following cyclic loading and at failure, stiffness during load to failure, and ultimate load of 16 tendon-prosthesis junctions using cadaveric canine flexor digitorum profundus tendons to re-create 2 junction techniques: the tendon loop (TL) and the polyester weave (PW). The TL junction showed greater percent stretch at a static load of 2 N, following 500 cycles of loading between 2 N and 50 N, and at peak load. The PW junction displayed greater stiffness from 50 to 150 N during load to failure. Both junctions failed at a mean ultimate load greater than 220 N. The described proximal junction techniques for active tendon implants were strong enough to resist early active motion in the immediate postoperative period without significant elongation. The PW technique displayed greater stiffness and ultimate load compared with the TL. Data on tendon-prosthesis characteristics of these 2 methods may aid the surgeon in choosing which junction technique to use, during surgical tensioning decisions, and in considering activity protocols after surgery. These data may also serve as a baseline for further investigations regarding active tendon implants. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  6. Increased unilateral tendon stiffness and its effect on gait 2-6 years after Achilles tendon rupture.

    Science.gov (United States)

    Agres, A N; Duda, G N; Gehlen, T J; Arampatzis, A; Taylor, W R; Manegold, S

    2015-12-01

    Achilles tendon rupture (ATR) alters tissue composition, which may affect long-term tendon mechanics and ankle function during movement. However, a relationship between Achilles tendon (AT) properties and ankle joint function during gait remains unclear. The primary hypotheses were that (a) post-ATR tendon stiffness and length differ from the noninjured contralateral side and that (b) intra-patient asymmetries in AT properties correlate to ankle function asymmetries during gait, determined by ankle angles and moments. Ultrasonography and dynamometry were used to assess AT tendon stiffness, strain, elongation, and rest length in both limbs of 20 ATR patients 2-6 years after repair. Three-dimensional ankle angles and moments were determined using gait analysis. Injured tendons exhibited increased stiffness, rest length, and altered kinematics, with higher dorsiflexion and eversion, and lower plantarflexion and inversion. Intra-patient tendon stiffness and tendon length ratios were negatively correlated to intra-patient ratios of the maximum plantarflexion moment and maximum dorsiflexion angle, respectively. These results suggest that after surgical ATR repair, higher AT stiffness, but not a longer AT, may contribute to deficits in plantarflexion moment generation. These data further support the claim that post-ATR tendon regeneration results in the production of a tissue that is functionally different than noninjured tendon. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. A ganglion of the patellar tendon in patellar tendon-lateral femoral condyle friction syndrome.

    Science.gov (United States)

    Touraine, Sébastien; Lagadec, Matthieu; Petrover, David; Genah, Idan; Parlier-Cuau, Caroline; Bousson, Valérie; Laredo, Jean-Denis

    2013-09-01

    Intratendinous ganglia are rare. We report the case of a sedentary woman with chronic mechanical anterolateral pain of the knee and an extensive ganglion of the patellar tendon as indicated on magnetic resonance (MR) and ultrasound (US) examinations. There was evidence of a high-riding patella, patellar malalignment and patellar tendon-lateral femoral condyle friction syndrome with significantly close contact between the patellar tendon and the lateral facet of the femoral trochlea. The ultrasound-guided aspiration of the ganglion enabled a localized injection of an anti-inflammatory drug (cortivazol) and the cytopathological examination of the fluid, which confirmed the diagnosis. Clinical improvement was maintained with knee rehabilitation and was satisfactory at follow-up after 1 year. To our knowledge, we report the first case of a ganglion of the patellar tendon subsequent to patellar tendon-lateral femoral condyle friction syndrome. We found that this case was illustrative of mucoid degeneration in connective tissue due to chronic repetitive microtraumas. Additionally, this case provided the opportunity to discuss the management of this condition in a sedentary individual with a high-riding patella and patellar malalignment.

  8. Augmented Repair of Acute Achilles Tendon Rupture Using an Allograft Tendon Weaving Technique.

    Science.gov (United States)

    Huang, Xiaowei; Huang, Gan; Ji, Ying; Ao, Rong guang; Yu, Baoqing; Zhu, Ya Long

    2015-01-01

    Achilles tendon rupture is a common injury, especially in those who are physically active. Although open surgery is a widely used option for the treatment of acute Achilles tendon rupture, the optimal treatment is still disputed. In our study, 59 patients with unilateral, closed, acute rupture of the Achilles tendon were treated by open surgery using an allograft weave to augment the repair. All the surgeries were performed within 1 to 4 days after injury. The mean American Orthopaedic Foot and Ankle Society ankle-hindfoot score was recorded as 91.20 (range 88 to 95), 95.34 (range 92 to 98), and 98.27 (range 97 to 99) at the 3-, 6-, and 12-month follow-up visit, respectively. At the final follow-up visit, the mean difference between the mid-calf circumference of the injured and uninjured legs was 0.19 (range -0.03 to 1.50) cm (p = .43). At the final follow-up visit, the mean difference between the vertical distances from the plantar surface of the heel to the ground for the injured and uninjured lower extremities was 0.44 (range -0.03 to 0.5) cm (p = .17). Augmented repair using the allograft tendon weaving technique provided satisfactory tendon strength and functional outcomes and a timely return to the patients' activities. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  9. Ultrasonography and Low-field Magnetic Resonance Imaging of the Common Calcanean Tendon in a Rabbit Model for Tendinopathy Research: a Descriptive Study of Normal Anatomy.

    Science.gov (United States)

    Skalec, A; Przyborowska-Zhalniarovich, P; Janus, I; Kirstein, K; Mieszkowska, M; Adamiak, Z; Chrószcz, A; Janeczek, M

    2016-09-01

    In spite of recent advances in treatment protocols, tendinopathies continue to challenge orthopaedists and surgeons. Due to the complexity of both tendon injuries and the healing processes, animal models are essential for addressing fundamental questions in tendinopathy research. Diagnostic imaging could contribute to the evaluation of animal models, thus providing information, which could be translated to human tendinopathies. The objective of our study was to evaluate in situ appearance of the rabbit common calcanean tendon with ultrasonography and magnetic resonance imaging. Additionally, we sought to assess and compare the feasibility and usefulness of these techniques in a rabbit model while focusing on the imaging of the particular structures involved in calcaneal tendon disorders. Eight California rabbits were used for post-mortem sonographic and low-field magnetic resonance examination. Morphometry was performed on longitudinal sonograms and sagittal MRI scans. The craniocaudal diameter of the tendon was measured at four points of interest. Ultrasonography and magnetic resonance provided good visualisation of the tendon origin, the paratenon and the pre-Achilles fat pad. Magnetic resonance images presented in more detail the structure of the calcaneal insertion. Both modalities failed to visualise the individual components of the common calcanean tendon and the bursa of the calcaneal tendon. Statistical analysis of measurements obtained showed that the craniocaudal diameter of the common calcanean tendon in a rabbit increases significantly with a growing length from the calcaneal tuber. Both magnetic resonance and ultrasonography are feasible, and should be considered complementary, not alternative imaging techniques in a rabbit common calcanean tendon model.

  10. Bifurcated intraarticular long head of biceps tendon

    Directory of Open Access Journals (Sweden)

    Vivek Pandey

    2014-01-01

    Full Text Available Though rare, many anomalous origins of long head of the biceps tendon (LHBT have been reported in the literature. Anatomic variations commonly explained are a third humeral head, anomalous insertion, congenital absence and adherence to the rotator cuff. We report a rare case who underwent shoulder arthroscopy with impingement symptoms where in LHBT was found to be bifurcated with a part attached to superior labrum and the other part to the posterior capsule of joint. Furthermore, intraarticular portion of LHBT was adherent to the undersurface of the supraspinatus tendon. Awareness of such an anatomical aberration during the shoulder arthroscopy is of great importance as it can potentially avoid unnecessary confusion and surgery.

  11. Motor responses to experimental Achilles tendon pain

    DEFF Research Database (Denmark)

    Henriksen, Marius; Aaboe, Jens; Graven-Nielsen, Thomas

    2011-01-01

    different days separated by 1 week, three-dimensional ground reaction forces, ankle joint kinematics and surface electromyography (EMG) of the lower leg muscles were recorded during one-legged full weight-bearing ankle plantar (concentric) and dorsal (eccentric) flexion exercises. Measurements were done...... before, during and after either experimental Achilles tendon pain or a non-painful control condition. Pain was induced by intratendinous injections of hypertonic saline with isotonic saline injections as control. Joint kinematics, ground reaction force frequency contents and average EMG amplitudes were...... calculated. Results Compared with the control condition experimental Achilles tendon pain reduced the EMG activity in agonistic, synergistic and antagonistic muscles, and increased the ground reaction force frequency content around 10 Hz, during both eccentric and concentric movement phases. Conclusions...

  12. [Animal experiment study of healing of the sutured flexor tendon].

    Science.gov (United States)

    Martini, A K; Blimke, B

    1992-01-01

    The purpose of the present study was to determine whether tendons contain intrinsic cells capable of repair. To accomplish this, rabbit flexor tendons were exposed microsurgically, cut through, resutured and transferred as free transplant into the knee-joint. Immobilisation of the knee-joint will cause progressive formation of adhesions permitting neovascularisation of the transplant. Both is not observed when sutured flexor tendons were put in a knee articulation with full range of joint motion. Transmission electron micrography revealed up to 8 weeks after implantation vital cells and incidences of collagen neosynthesis independently whether adhesions existed or not. Histologically intrinsic repair was confirmed in mobile transplants and mainly initiated by cells of the visceral synovial sheet which form an anatomic-surgical unity with the tendon. In conclusion the importance of the synovial fluid for the tendon nutrition is underlined by the fact that an intrinsic healing of flexor tendon is possible without formation of adhesions.

  13. Effect of aging and exercise on the tendon

    DEFF Research Database (Denmark)

    Svensson, Rene B; Heinemeier, Katja Maria; Couppé, Christian

    2016-01-01

    in humans, which likely reflects synthesis at the very periphery of the tendon rather than the core. Average collagen fibril diameter is largely unaffected by exercise, while there can be some hypertrophy of the whole tendon. In addition, it seems that resistance training can yield increased stiffness......Here, we review the literature on how tendons respond and adapt to ageing and exercise. With respect to aging, there are considerable changes early in life, but this seems to be maturation rather than aging per se. In vitro data indicate that aging is associated with a decreased potential for cell...... proliferation and a reduction in the number of stem/progenitor-like cells. Further, there is persuasive evidence that turnover in the core of the tendon after maturity is very slow or absent. Tendon fibril diameter, collagen content, and whole tendon size appear to be largely unchanged with aging, while...

  14. Congenital extensor tendon dislocation causing pseudotriggering of the little finger

    Directory of Open Access Journals (Sweden)

    Meriç Çırpar

    2017-10-01

    Full Text Available The main complaints in extensor tendon dislocations are pain, swelling, sense of discomfort, snapping and difficulty in writing and forceful flexion. However, congenital extensor tendon subluxations may present with triggering of the fingers due to tendon dislocations. Unnecessary A1 pulley release may be performed for pseudotriggerring with unsuccessful results. Here, we report an unusual case of congenital extensor tendon subluxation of multiple digits with triggering of the left little finger and aim to attract notice to pseudotriggering of the digits due to tendon dislocations. An extensor hood reconstruction performed by an extensor digitorum communis tendon slip which is passed beneath the deep intermetacarpal ligament is a successful choice of treatment for these patients.

  15. [Suture techniques and material in surgery of flexor tendons].

    Science.gov (United States)

    Pillukat, T; Fuhrmann, R; Windolf, J; van Schoonhoven, J

    2017-03-01

    Adhesions and scar formation between flexor tendons and the surrounding tissue are only contemporarily avoidable by movement of flexor tendons. Concepts with active follow-up protocols are more favorable than passive mobilization. The main risks of flexor tendon repair are rupture of the tendon suture, insidious gap formation and resistance to tendon gliding within the tendon sheath. Currently, there is no consensus with respect to the optimal suture technique or suture material. Nevertheless, there are some principles worth paying attention to, such as using stronger suture material, blocking stitches, suture techniques with four or more strands as well as circular running sutures. A technically acceptable compromise, even for the less experienced, is currently the four-strand suture combined with a circular running suture. It maintains sufficient stability for active motion follow-up protocols without resistance.

  16. Engineering tendon and ligament tissues: present developments towards successful clinical products.

    Science.gov (United States)

    Rodrigues, Márcia T; Reis, Rui L; Gomes, Manuela E

    2013-09-01

    Musculoskeletal diseases are one of the leading causes of disability worldwide. Among them, tendon and ligament injuries represent an important aspect to consider in both athletes and active working people. Tendon and ligament damage is an important cause of joint instability, and progresses into early onset of osteoarthritis, pain, disability and eventually the need for joint replacement surgery. The social and economical burden associated with these medical conditions presents a compelling argument for greater understanding and expanding research on this issue. The particular physiology of tendons and ligaments (avascular, hypocellular and overall structural mechanical features) makes it difficult for currently available treatments to reach a complete and long-term functional repair of the damaged tissue, especially when complete tear occurs. Despite the effort, the treatment modalities for tendon and ligament are suboptimal, which have led to the development of alternative therapies, such as the delivery of growth factors, development of engineered scaffolds or the application of stem cells, which have been approached in this review. Copyright © 2012 John Wiley & Sons, Ltd.

  17. High stress monitoring of prestressing tendons in nuclear concrete vessels using fibre-optic sensors

    Energy Technology Data Exchange (ETDEWEB)

    Perry, M., E-mail: marcus.perry@strath.ac.uk [Institute for Energy and Environment, University of Strathclyde, 204 George Street, Glasgow G1 1XW (United Kingdom); Yan, Z.; Sun, Z.; Zhang, L. [Aston Institute of Photonic Technologies, Aston University, Birmingham B4 7ET (United Kingdom); Niewczas, P. [Institute for Energy and Environment, University of Strathclyde, 204 George Street, Glasgow G1 1XW (United Kingdom); Johnston, M. [Civil Design Group, EDF Energy, Nuclear Generation, East Kilbride G74 5PG (United Kingdom)

    2014-03-15

    Highlights: • We weld radiation-resistant optical fibre strain sensors to steel prestressing tendons. • We prove the sensors can survive 1300 MPa stress (80% of steel's tensile strength). • Mechanical relaxation of sensors is characterised under 1300 MPa stress over 10 h. • Strain transfer between tendon and sensor remains at 69% after relaxation. • Sensors can withstand and measure deflection of tendon around a 4.5 m bend radius. - Abstract: Maintaining the structural health of prestressed concrete nuclear containments is a key element in ensuring nuclear reactors are capable of meeting their safety requirements. This paper discusses the attachment, fabrication and characterisation of optical fibre strain sensors suitable for the prestress monitoring of irradiated steel prestressing tendons. The all-metal fabrication and welding process allowed the instrumented strand to simultaneously monitor and apply stresses up to 1300 MPa (80% of steel's ultimate tensile strength). There were no adverse effects to the strand's mechanical properties or integrity. After sensor relaxation through cyclic stress treatment, strain transfer between the optical fibre sensors and the strand remained at 69%. The fibre strain sensors could also withstand the non-axial forces induced as the strand was deflected around a 4.5 m bend radius. Further development of this technology has the potential to augment current prestress monitoring practices, allowing distributed measurements of short- and long-term prestress losses in nuclear prestressed-concrete vessels.

  18. Effects of no stiffness inside unbonded tendon ducts on the behavior of prestressd concrete containment vessels

    Energy Technology Data Exchange (ETDEWEB)

    Noh, Sang Hoon; Kwak, Hyo Gyong [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Jung, Rae Young; Noh, Sang Hoon [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2016-06-15

    The numerical simulation methodologies to evaluate the structural behaviors of prestressed concrete containment vessels (PCCVs) have been substantially developed in recent decades. However, there remain several issues to be investigated more closely to narrow the gap between test results and numerical simulations. As one of those issues, the effects of no stiffness inside unbonded tendon ducts on the behavior of PCCVs are investigated in this study. Duct holes for prestressing cables' passing are provided inside the containment wall and dome in one to three directions for general PCCVs. The specific stress distribution along the periphery of the prestressing duct hole and the loss of stiffness inside the hole, especially in an unbonded tendon system, are usually neglected in the analysis of PCCVs with the assumption that the duct hole is filled with concrete. However, duct holes are not small enough to be neglected. In this study, the effects of no stiffness inside the unbonded tendon system on the behaviors of PCCVs are evaluated using both analytical and numerical approaches. From the results, the effects of no stiffness in unbonded tendons need to be considered in numerical simulations for PCCVs, especially under internal pressure loading.

  19. Fourier-transform infrared anisotropy in cross and parallel sections of tendon and articular cartilage

    Directory of Open Access Journals (Sweden)

    Bidthanapally Aruna

    2008-10-01

    Full Text Available Abstract Background Fourier Transform Infrared Imaging (FTIRI is used to investigate the amide anisotropies at different surfaces of a three-dimensional cartilage or tendon block. With the change in the polarization state of the incident infrared light, the resulting anisotropic behavior of the tissue structure is described here. Methods Thin sections (6 μm thick were obtained from three different surfaces of the canine tissue blocks and imaged at 6.25 μm pixel resolution. For each section, infrared imaging experiments were repeated thirteen times with the identical parameters except a 15° increment of the analyzer's angle in the 0° – 180° angular space. The anisotropies of amide I and amide II components were studied in order to probe the orientation of the collagen fibrils at different tissue surfaces. Results For tendon, the anisotropy of amide I and amide II components in parallel sections is comparable to that of regular sections; and tendon's cross sections show distinct, but weak anisotropic behavior for both the amide components. For articular cartilage, parallel sections in the superficial zone have the expected infrared anisotropy that is consistent with that of regular sections. The parallel sections in the radial zone, however, have a nearly isotropic amide II absorption and a distinct amide I anisotropy. Conclusion From the inconsistency in amide anisotropy between superficial to radial zone in parallel section results, a schematic model is used to explain the origins of these amide anisotropies in cartilage and tendon.

  20. Extensor mechanism of the knee: MR imaging of tendon injuries; Sistema extensor do joelho: ressonancia magnetica das lesoes tendinosas

    Energy Technology Data Exchange (ETDEWEB)

    Torriani, Martin; Maeda, Lucimara; Cerqueira, Elza M.F.P.; Montandon, Cristiano; Zanardi, Veronica A. [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Ciencias Medicas. Dept. de Radiologia

    2000-04-01

    The authors describe the normal MR imaging appearance of the extensor tendons of the knee and the lesions that may affect these structures. MR imaging was performed in patients presenting with a variety of injuries of the extensor mechanism of the knee. MR imaging is the method of choice to evaluate tendon injuries, due to its high anatomic resolution. The knowledge of the normal anatomy and the recognition of the spectrum of the injuries that involve these structures are important for an early diagnosis and appropriate management of these patients. (author)

  1. Biceps femoris tendon injuries sustained while playing hockey

    OpenAIRE

    Watura, Christopher; Harries, William

    2011-01-01

    A 42-year-old female nurse presented in March 2008 with a left proximal hamstring tendon injury sustained while playing hockey. At surgery, the proximal biceps femoris tendon and semitendonosus were found to be ruptured and were repaired. The patient made a good recovery but sustained a further hockey injury in January 2010 involving a complete tear and rupture of the biceps femoris tendon distally. This was managed conservatively and the patient was able to return to playing hockey 10 months...

  2. Hamstring Tendon Regeneration After Harvesting: A Systematic Review.

    Science.gov (United States)

    Suijkerbuijk, Mathijs A M; Reijman, Max; Lodewijks, Susanne J M; Punt, Jorien; Meuffels, Duncan E

    2015-10-01

    Hamstring tendons are often used as autografts for anterior cruciate ligament (ACL) reconstruction. However, no systematic review has been performed describing consequences such as hamstring tendon regeneration rate and determinants of hamstring tendon regeneration. To summarize the current literature regarding hamstring tendon rate regeneration, the time course of regeneration, and determinants of hamstring regeneration. Systematic review. A search was performed in the Embase, Medline (OvidSP), Web of Science, Cochrane, PubMed, and Google Scholar databases up to June 2014 to identify relevant articles. A study was eligible if it met the following inclusion criteria: tendons were harvested, regeneration at harvest site was assessed, population size was at least 10 human subjects, full-text article was available, and the study design was either a randomized controlled trial, prospective cohort study, retrospective cohort study, or case control study. A risk of bias assessment of the eligible articles was determined. Data describing hamstring tendon regeneration rates were pooled per time period. A total of 18 publications met the inclusion criteria. The mean regeneration rate for the semitendinosus and gracilis tendons was, in all cases, 70% or higher. More than 1 year after harvesting, 79% (median [IQR], 80 [75.5-90]) of the semitendinosus tendons and 72% (median [IQR], 80 [61-88.5]) of the gracilis tendons were regenerated. No significant differences in regeneration rate could be found considering patient sex, age, height, weight, or duration of immobilization. Results did not clearly show whether absence of regeneration disadvantages the subsequent hamstring function. Five studies measured the regeneration rate at different moments in time. Hamstring tendons regenerated in the majority of patients after ACL reconstruction. The majority of the hamstring tendon regeneration was found to occur between 1 month and 1 year after harvest. No significant determinants for

  3. Inflammation activation and resolution in human tendon disease

    OpenAIRE

    Dakin, Stephanie G; Martinez, Fernando O; Yapp, Clarence; Wells, Graham; Oppermann, Udo; Dean, Benjamin JF; Smith, Richard DJ; Wheway, Kim; Watkins, Bridget; Roche, Lucy; Carr, Andrew J

    2015-01-01

    Improved understanding of the role of inflammation in tendon disease is required to facilitate therapeutic target discovery. We studied supraspinatus tendons from patients experiencing pain before and after surgical subacromial decompression treatment. Tendons were classified as having early, intermediate or advanced disease and inflammation was characterized through activation of pathways mediated by Interferon, NF-κB, glucocorticoid receptor and STAT-6. Inflammation signatures revealed expr...

  4. Isolated tear of the plantaris tendon: ultrasound and MRI appearance

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, Stefano [CIM, Cabinet Imagerie Medicale, Geneva (Switzerland); Sailly, Matthieu [CIM, Cabinet Imagerie Medicale, Geneva (Switzerland); Health Center, ASPIRE, Doha (Qatar); Molini, Lucio [Ospedale Galliera, Struttura complessa di Radiodiagnostica, Genova (Italy)

    2011-07-15

    We report a retrospective analysis of the ultrasound and magnetic resonance imaging appearance of five patients with isolated plantaris tendon tears. Both imaging techniques allowed detection of the tear, assessment of its severity and of its location. Compared with magnetic resonance imaging, ultrasound resulted in a less expensive and time-consuming evaluation. Isolated plantaris tendon tears can clinically mimic Achilles tendon tears or thrombophlebitis. Unlike these conditions, plantaris tear has a benign outcome and does not need surgical treatment or anticoagulation. (orig.)

  5. Foot and ankle kinematics in rheumatoid arthritis: influence of foot and ankle joint and leg tendon pathologies.

    Science.gov (United States)

    Dubbeldam, R; Baan, H; Nene, A V; Drossaers-Bakker, K W; van de Laar, M A F J; Hermens, H J; Buurke, J H

    2013-04-01

    From early onset of the disease, patients with rheumatoid arthritis (RA) experience walking impairments. Pathologic effects of RA on foot and ankle structures have been studied clinically, but little is known as to how they relate to kinematic changes during gait. The aim of this study was to explore the relationship between clinically observed pathologies of foot and ankle joints and leg tendons and the corresponding gait kinematics. The gait of 25 subjects with varying stages of RA was recorded and foot and ankle kinematics were assessed. Magnetic resonance imaging was performed for each subject: first metatarsophalangeal (MTP) joint, midfoot, and hindfoot synovitis, erosion scores, and leg tendon involvement were determined. The joint alignment and motion score represented daily clinical assessment. The 95% confidence intervals of the Spearman's correlation coefficient tests were used to explore the relationships between the clinical and kinematic parameters. Maximum first MTP joint dorsiflexion at preswing was related to reduced first MTP joint passive motion, first MTP joint synovitis and erosion, midfoot synovitis and erosion, and hindfoot erosion. Midfoot pronation range of motion during single stance was related to subtalar alignment and Achilles tendon involvement. Hindfoot eversion range of motion during single stance was related to subtalar alignment and peroneus longus tendon involvement. Involvement of the tibialis posterior tendon could not be identified as an independent factor influencing foot or ankle kinematics. Our findings suggest moderate to strong relationships between foot and ankle gait kinematics and structural pathologies. Copyright © 2013 by the American College of Rheumatology.

  6. Use of the semitendinosus tendon for foot and ankle tendon reconstructions,

    Directory of Open Access Journals (Sweden)

    Frederico Lutti Guerra de Aguiar Zink

    2014-10-01

    Full Text Available Objective:To demonstrate the results obtained from foot and ankle tendon reconstructions using the tendon of the semitendinosus muscle. The clinical results, the patient's degree of satisfaction and complications in the graft donor and recipient areas were evaluated.Methods:This was a retrospective study in which the medical files of 38 patients who underwent this surgical procedure between 2006 and 2010 were surveyed. The functional results from this technique, the complications in the donor and recipient areas and the patients' degree of satisfaction were evaluated.Results:Three patients presented complications in the recipient area (skin necrosis; one patient showed complications in the donor area (pain and insensitivity; and all patients had satisfactory functional results, with complete range of motion.Conclusion:The semitendinosus muscle is a good option for treatments for foot and ankle tendon injuries.

  7. The histology of tendon attachments to bone in man.

    OpenAIRE

    Benjamin, M.; Evans, E. J.; Copp, L

    1986-01-01

    Based on a parallel study of a wide range of human tendons from embalmed dissecting room subjects and from a study of dried bones, an explanation is offered for the well known similarity in gross appearance between the markings left by certain tendons (e.g. those of the rotator cuff) and by articular surfaces on dried bones. Epiphyseal tendons leave markings on bones that look like those left by articular surfaces. These tendons have a prominent zone of fibrocartilage at their attachment site...

  8. Biology and augmentation of tendon-bone insertion repair

    Directory of Open Access Journals (Sweden)

    Lui PPY

    2010-08-01

    Full Text Available Abstract Surgical reattachment of tendon and bone such as in rotator cuff repair, patellar-patella tendon repair and anterior cruciate ligament (ACL reconstruction often fails due to the failure of regeneration of the specialized tissue ("enthesis" which connects tendon to bone. Tendon-to-bone healing taking place between inhomogenous tissues is a slow process compared to healing within homogenous tissue, such as tendon to tendon or bone to bone healing. Therefore special attention must be paid to augment tendon to bone insertion (TBI healing. Apart from surgical fixation, biological and biophysical interventions have been studied aiming at regeneration of TBI healing complex, especially the regeneration of interpositioned fibrocartilage and new bone at the healing junction. This paper described the biology and the factors influencing TBI healing using patella-patellar tendon (PPT healing and tendon graft to bone tunnel healing in ACL reconstruction as examples. Recent development in the improvement of TBI healing and directions for future studies were also reviewed and discussed.

  9. Asymmetrical Achilles tendon ossification and rare rear heel pain

    Directory of Open Access Journals (Sweden)

    Md Abu Bakar Siddiq

    2017-03-01

    Full Text Available Achilles tendon ossification is not a frequent association of posterior heel pain in pain physicians’ daily practice. The condition has been reportedly common following rear heel trauma (repetitive heel stress injury, surgery (club foot surgery; however, some endocrino-metabolic, haematological disorders can also contribute to Achilles tendon ossification. Shape of ossified tendon mass varies from discrete (single/multiple to extensive variety; and as per literature review, in bilateral cases they are alike. To be intriguing, here in this write-up, we demonstrate asymmetrical (in terms of clinical features and radioimaging findings, bilateral Achilles tendon ossification in a 70-year-old retired farmer, first time in literature.

  10. Engineering Tendon: Scaffolds, Bioreactors, and Models of Regeneration.

    Science.gov (United States)

    Youngstrom, Daniel W; Barrett, Jennifer G

    2016-01-01

    Tendons bridge muscle and bone, translating forces to the skeleton and increasing the safety and efficiency of locomotion. When tendons fail or degenerate, there are no effective pharmacological interventions. The lack of available options to treat damaged tendons has created a need to better understand and improve the repair process, particularly when suitable autologous donor tissue is unavailable for transplantation. Cells within tendon dynamically react to loading conditions and undergo phenotypic changes in response to mechanobiological stimuli. Tenocytes respond to ultrastructural topography and mechanical deformation via a complex set of behaviors involving force-sensitive membrane receptor activity, changes in cytoskeletal contractility, and transcriptional regulation. Effective ex vivo model systems are needed to emulate the native environment of a tissue and to translate cell-matrix forces with high fidelity. While early bioreactor designs have greatly expanded our knowledge of mechanotransduction, traditional scaffolds do not fully model the topography, composition, and mechanical properties of native tendon. Decellularized tendon is an ideal scaffold for cultivating replacement tissue and modeling tendon regeneration. Decellularized tendon scaffolds (DTS) possess high clinical relevance, faithfully translate forces to the cellular scale, and have bulk material properties that match natural tissue. This review summarizes progress in tendon tissue engineering, with a focus on DTS and bioreactor systems.

  11. Engineering Tendon: Scaffolds, Bioreactors, and Models of Regeneration

    Directory of Open Access Journals (Sweden)

    Daniel W. Youngstrom

    2016-01-01

    Full Text Available Tendons bridge muscle and bone, translating forces to the skeleton and increasing the safety and efficiency of locomotion. When tendons fail or degenerate, there are no effective pharmacological interventions. The lack of available options to treat damaged tendons has created a need to better understand and improve the repair process, particularly when suitable autologous donor tissue is unavailable for transplantation. Cells within tendon dynamically react to loading conditions and undergo phenotypic changes in response to mechanobiological stimuli. Tenocytes respond to ultrastructural topography and mechanical deformation via a complex set of behaviors involving force-sensitive membrane receptor activity, changes in cytoskeletal contractility, and transcriptional regulation. Effective ex vivo model systems are needed to emulate the native environment of a tissue and to translate cell-matrix forces with high fidelity. While early bioreactor designs have greatly expanded our knowledge of mechanotransduction, traditional scaffolds do not fully model the topography, composition, and mechanical properties of native tendon. Decellularized tendon is an ideal scaffold for cultivating replacement tissue and modeling tendon regeneration. Decellularized tendon scaffolds (DTS possess high clinical relevance, faithfully translate forces to the cellular scale, and have bulk material properties that match natural tissue. This review summarizes progress in tendon tissue engineering, with a focus on DTS and bioreactor systems.

  12. Nanoparticles for tendon healing and regeneration: literature review.

    Directory of Open Access Journals (Sweden)

    Paolo Domenico Parchi

    2016-08-01

    Full Text Available Tendon injuries are commonly met in the emergency department. Unfortunately, tendon tissue has limited regeneration potential and usually the consequent formation of scar tissue causes inferior mechanical properties Nanoparticles could be used in different way to improve tendon healing and regeneration, ranging from scaffolds manufacturing (increasing the strength and endurance or anti-adhesions, anti-microbial and anti-inflammatory properties to gene therapy. This paper aims to summarize the most relevant studies showing the potential application of nanoparticles for tendon tissue regeneration

  13. A novel postoperative immobilization model for murine Achilles tendon sutures.

    Science.gov (United States)

    Shibuya, Yoichiro; Takayama, Yuzo; Kushige, Hiroko; Jacinto, Sandra; Sekido, Mitsuru; Kida, Yasuyuki S

    2016-08-01

    The body's motion and function are all in part effected by a vital tissue, the tendon. Tendon injury often results in limited functioning after postoperative procedures and even for a long time after rehabilitation. Although numerous studies have reported surgical procedures using animal models which have contributed to both basic and clinical research, modeling of tendon sutures or postoperative immobilizations has not been performed on small experimental animals, such as mice. In this study we have developed an easy Achilles tendon suture and postoperative ankle fixation model in a mouse. Right Achilles tendons were incised and 10-0 nylons were passed through the proximal and distal ends using a modified Kessler method. Subsequently, the right ankle was immobilized in a plantarflexed position with novel splints, which were made from readily available extension tubes. Restriction of the tendon using handmade splints reduced swelling, as opposed to fixating with the usual plaster of Paris. Using this method, the usage of the right Achilles tendons began on postoperative days 13.5 ± 4.6, which indicated healing within two weeks. Therefore our simple short-term murine Achilles tendon suture procedure is useful for studying immediate tendon repair mechanisms in various models, including genetically-modified mice. © The Author(s) 2015.

  14. Tendon progenitor cells in injured tendons have strong chondrogenic potential: the CD105-negative subpopulation induces chondrogenic degeneration.

    Science.gov (United States)

    Asai, Shuji; Otsuru, Satoru; Candela, Maria Elena; Cantley, Leslie; Uchibe, Kenta; Hofmann, Ted J; Zhang, Kairui; Wapner, Keith L; Soslowsky, Louis J; Horwitz, Edwin M; Enomoto-Iwamoto, Motomi

    2014-12-01

    To study the cellular mechanism of the tendon repair process, we used a mouse Achilles tendon injury model to focus on the cells recruited to the injured site. The cells isolated from injured tendon 1 week after the surgery and uninjured tendons contained the connective tissue progenitor populations as determined by colony-forming capacity, cell surface markers, and multipotency. When the injured tendon-derived progenitor cells (inTPCs) were transplanted into injured Achilles tendons, they were not only integrated in the regenerating area expressing tenogenic phenotype but also trans-differentiated into chondrogenic cells in the degenerative lesion that underwent ectopic endochondral ossification. Surprisingly, the micromass culture of the inTPCs rapidly underwent chondrogenic differentiation even in the absence of exogenous bone morphogenetic proteins or TGFβs. The cells isolated from human ruptured tendon tissues also showed connective tissue progenitor properties and exhibited stronger chondrogenic ability than bone marrow stromal cells. The mouse inTPCs contained two subpopulations one positive and one negative for CD105, a coreceptor of the TGFβ superfamily. The CD105-negative cells showed superior chondrogenic potential in vitro and induced larger chondroid degenerative lesions in mice as compared to the CD105-positive cells. These findings indicate that tendon progenitor cells are recruited to the injured site of tendons and have a strong chondrogenic potential and that the CD105-negative population of these cells would be the cause for chondroid degeneration in injured tendons. The newly identified cells recruited to the injured tendon may provide novel targets to develop therapeutic strategies to facilitate tendon repair. © 2014 AlphaMed Press.

  15. In vivo passive mechanical behaviour of muscle fascicles and tendons in human gastrocnemius muscle-tendon units.

    Science.gov (United States)

    Herbert, Robert D; Clarke, Jillian; Kwah, Li Khim; Diong, Joanna; Martin, Josh; Clarke, Elizabeth C; Bilston, Lynne E; Gandevia, Simon C

    2011-11-01

    Ultrasound imaging was used to measure the length of muscle fascicles in human gastrocnemius muscles while the muscle was passively lengthened and shortened by moving the ankle. In some subjects the muscle belly 'buckled' at short lengths. When the gastrocnemius muscle-tendon unit was passively lengthened from its shortest in vivo length by dorsiflexing the ankle, increases in muscle-tendon length were not initially accompanied by increases in muscle fascicle lengths (fascicle length remained constant), indicating muscle fascicles were slack at short muscle-tendon lengths. The muscle-tendon length at which slack is taken up differs among fascicles: some fascicles begin to lengthen at very short muscle-tendon lengths whereas other fascicles remain slack over a large range of muscle-tendon lengths. This suggests muscle fascicles are progressively 'recruited' and contribute sequentially to muscle-tendon stiffness during passive lengthening of the muscle-tendon unit. Even above their slack lengths muscle fascicles contribute only a small part (tendon length. The contribution of muscle fascicles to muscle-tendon length increases with muscle length. The novelty of this work is that it reveals a previously unrecognised phenomenon (buckling at short lengths), posits a new mechanism of passive mechanical properties of muscle (recruitment of muscle fascicles), and confirms with high-resolution measurements that the passive compliance of human gastrocnemius muscle-tendon units is due largely to the tendon. It would be interesting to investigate if adaptations of passive properties of muscles are associated with changes in the distribution of muscle lengths at which fascicles fall slack.

  16. The promoting effect of pentadecapeptide BPC 157 on tendon healing involves tendon outgrowth, cell survival, and cell migration.

    Science.gov (United States)

    Chang, Chung-Hsun; Tsai, Wen-Chung; Lin, Miao-Sui; Hsu, Ya-Hui; Pang, Jong-Hwei Su

    2011-03-01

    Pentadecapeptide BPC 157, composed of 15 amino acids, is a partial sequence of body protection compound (BPC) that is discovered in and isolated from human gastric juice. Experimentally it has been demonstrated to accelerate the healing of many different wounds, including transected rat Achilles tendon. This study was designed to investigate the potential mechanism of BPC 157 to enhance healing of injured tendon. The outgrowth of tendon fibroblasts from tendon explants cultured with or without BPC 157 was examined. Results showed that BPC 157 significantly accelerated the outgrowth of tendon explants. Cell proliferation of cultured tendon fibroblasts derived from rat Achilles tendon was not directly affected by BPC 157 as evaluated by MTT assay. However, the survival of BPC 157-treated cells was significantly increased under the H(2)O(2) stress. BPC 157 markedly increased the in vitro migration of tendon fibroblasts in a dose-dependent manner as revealed by transwell filter migration assay. BPC 157 also dose dependently accelerated the spreading of tendon fibroblasts on culture dishes. The F-actin formation as detected by FITC-phalloidin staining was induced in BPC 157-treated fibroblasts. The protein expression and activation of FAK and paxillin were determined by Western blot analysis, and the phosphorylation levels of both FAK and paxillin were dose dependently increased by BPC 157 while the total amounts of protein was unaltered. In conclusion, BPC 157 promotes the ex vivo outgrowth of tendon fibroblasts from tendon explants, cell survival under stress, and the in vitro migration of tendon fibroblasts, which is likely mediated by the activation of the FAK-paxillin pathway.

  17. Twelve-month outcomes following surgical repair of the Achilles tendon.

    Science.gov (United States)

    Fox, G; Gabbe, B J; Richardson, M; Oppy, A; Page, R; Edwards, E R; Hau, R; Ekegren, C L

    2016-10-01

    Incidence of Achilles tendon rupture (ATR) has increased over recent years, and debate regarding optimal management has been widely documented. Most papers have focused on surgical success, complications and short term region-specific outcomes. Inconsistent use of standardised outcome measures following surgical ATR repair has made it difficult to evaluate the impact of ATR on a patient's health status post-surgery, and to compare this to other injury types. This study aimed to report the frequency of surgical repairs of the Achilles tendon over a five-year period within an orthopaedic trauma registry, and to investigate return to work (RTW) status, health status and functional outcomes at 12 months post-surgical repair of the Achilles tendon. Two hundred and four adults registered by the Victorian Orthopaedic Trauma Outcomes Registry (VOTOR) who underwent surgical repair of the Achilles tendon between July 2009 and June 2014 were included in this prospective cohort study. The Extended Glasgow Outcome Scale (GOS-E), 3-level European Quality of Life 5 Dimension measure (EQ-5D-3L), and RTW status 12 months following surgical ATR repair were collected through structured telephone interviews conducted by trained interviewers. At 12 months, 92% of patients were successfully followed up. Of those working prior to injury, 95% had returned to work. 42% of patients reported a full recovery on the GOS-E scale. The prevalence of problems on the EQ-5D-3L at 12 months was 0.5% for self-care, 11% for anxiety, 13% for mobility, 16% for activity, and 22% for pain. 16% of patients reported problems with more than one domain. The number of surgical repairs of the Achilles tendon within the VOTOR registry decreased by 68% over the five-year study period. Overall, patients recover well following surgical repair of the Achilles tendon. However, in this study, deficits in function persisted for over half of patients at 12 months post-injury. The decreased incidence of surgical Achilles

  18. The Effect of Phospholipids (Surfactant on Adhesion and Biomechanical Properties of Tendon: A Rat Achilles Tendon Repair Model

    Directory of Open Access Journals (Sweden)

    T. Kursat Dabak

    2015-01-01

    Full Text Available Adhesion of the tendon is a major challenge for the orthopedic surgeon during tendon repair. Manipulation of biological environment is one of the concepts to prevent adhesion. Lots of biochemicals have been studied for this purpose. We aimed to determine the effect of phospholipids on adhesion and biomechanical properties of tendon in an animal tendon repair model. Seventy-two Wistar rats were divided into 4 groups. Achilles tendons of rats were cut and repaired. Phospholipids were applied at two different dosages. Tendon adhesion was determined histopathologically and biomechanical test was performed. At macroscopic evaluation of adhesion, there are statistically significant differences between multiple-dose phospholipid injection group and Control group and also hyaluronic acid group and Control group (p0.008. Ultimate strength was highest at hyaluronic acid injection group and lowest at multiple-dose phospholipid injection group. Single-dose phospholipids (surfactant application may have a beneficial effect on the tendon adhesion. Although multiple applications of phospholipids seem the most effective regime to reduce the tendon adhesion among groups, it deteriorated the biomechanical properties of tendon.

  19. Science to Practice: Quantitative US Elastography Can Be Used to Quantify Mechanical and Histologic Tendon Healing in a Rabbit Model of Achilles Tendon Transection.

    Science.gov (United States)

    Lee, Kenneth S; Martin, Jack; Thelen, Darryl

    2017-05-01

    Compression-based ultrasonographic (US) elastography is associated with time-dependent mechanical and histologic changes of the healing tendon in a transected rabbit model of the Achilles tendon. This finding will lead to continued development of quantitative US, which can be used to objectively assess a diseased or healing tendon. With advances in the method used, clinical translation of tendon elastography may enable clinicians to diagnose tendon damage and track healing, which should improve both treatment and outcome.

  20. The development of zebrafish tendon and ligament progenitors

    Science.gov (United States)

    Chen, Jessica W.; Galloway, Jenna L.

    2014-01-01

    Despite the importance of tendons and ligaments for transmitting movement and providing stability to the musculoskeletal system, their development is considerably less well understood than that of the tissues they serve to connect. Zebrafish have been widely used to address questions in muscle and skeletal development, yet few studies describe their tendon and ligament tissues. We have analyzed in zebrafish the expression of several genes known to be enriched in mammalian tendons and ligaments, including scleraxis (scx), collagen 1a2 (col1a2) and tenomodulin (tnmd), or in the tendon-like myosepta of the zebrafish (xirp2a). Co-expression studies with muscle and cartilage markers demonstrate the presence of scxa, col1a2 and tnmd at sites between the developing muscle and cartilage, and xirp2a at the myotendinous junctions. We determined that the zebrafish craniofacial tendon and ligament progenitors are neural crest derived, as in mammals. Cranial and fin tendon progenitors can be induced in the absence of differentiated muscle or cartilage, although neighboring muscle and cartilage are required for tendon cell maintenance and organization, respectively. By contrast, myoseptal scxa expression requires muscle for its initiation. Together, these data suggest a conserved role for muscle in tendon development. Based on the similarities in gene expression, morphology, collagen ultrastructural arrangement and developmental regulation with that of mammalian tendons, we conclude that the zebrafish tendon populations are homologous to their force-transmitting counterparts in higher vertebrates. Within this context, the zebrafish model can be used to provide new avenues for studying tendon biology in a vertebrate genetic system. PMID:24803652

  1. In vitro and in vivo effects of PDGF-BB delivery strategies on tendon healing: a review.

    Science.gov (United States)

    Evrova, O; Buschmann, J

    2017-07-17

    To promote and support tendon healing, one viable strategy is the use or administration of growth factors at the wound/rupture site. Platelet derived growth factor-BB (PDGF-BB), together with other growth factors, is secreted by platelets after injury. PDGF-BB promotes mitogenesis and angiogenesis, which could accelerate tendon healing. Therefore, in vitro studies with PDGF-BB have been performed to determine its effect on tenocytes and tenoblasts. Moreover, accurate and sophisticated drug delivery devices, aiming for a sustained release of PDGF-BB, have been developed, either by using heparin-binding and fibrin-based matrices or different electrospinning techniques. In this review, the structure and composition, as well as the healing process of tendons, are described. Part A deals with in vitro studies. They focus on the multiple effects evoked by PDGF-BB on the cellular level. Moreover, they address strategies for the sustained delivery of PDGF-BB. Part B focuses on animal models used to test different delivery strategies for PDGF-BB, in the context of tendon reconstruction. These studies showed that dosage and timing of PDGF-BB application are the most important factors for deciding which delivery device should be applied for a specific tendon laceration.

  2. The role of the peroneal tendons in passive stabilisation of the ankle joint: an in vitro study.

    Science.gov (United States)

    Ziai, Pejman; Benca, Emir; von Skrbensky, Gobert; Graf, Alexandra; Wenzel, Florian; Basad, Erhan; Windhager, Reinhard; Buchhorn, Tomas

    2013-06-01

    Peroneal tendons are known as active stabilizer in acute ankle sprain while an intact ankle mortise and intact lateral ligaments are required for passive stability of the ankle joint. The goal of this study is to determine the peroneal tendons as passive stabilizer in case of lateral ligament instability. Twelve (12) human lower leg cadaver specimens underwent a torsion simulation in the testing system, 858 Mini Bionix(®) (MTS(®) Systems Corporation, Eden Prairie, MN, USA) and a specially designed mounting platform for the specimens. The preset torsion between tibia and calcaneus was primarily set at 30° of internal rotation during plantar flexion and hindfoot inversion. The resisting torque around mechanical tibial axis was recorded which ensures stability in ankle sprain trauma. The first series of measurements were performed on healthy specimens and the following after transecting structures in following order: ATFL (anterior talofibular ligament) in combination with CFL (calcaneofibular ligament), followed by peroneus longus tendon and finally peroneus brevis tendon. The combined lateral ATFL and CFL instability shows a decrease of the resisting torque which ensures stability in ankle sprain trauma. Only a transection of PLT with existing lateral dual-ligament instability results in a significant decrease in torque (p lesion in ankle sprain trauma. A deficiency in viscoelastic properties of the peroneus longus tendon must be considered in diagnostic and treatment for ankle instability.

  3. Human flexor tendon tissue engineering: decellularization of human flexor tendons reduces immunogenicity in vivo.

    Science.gov (United States)

    Raghavan, Shyam S; Woon, Colin Y L; Kraus, Armin; Megerle, Kai; Choi, Matthew S S; Pridgen, Brian C; Pham, Hung; Chang, James

    2012-04-01

    In mutilating hand injuries, tissue engineered tendon grafts may provide a reconstructive solution. We have previously described a method to decellularize cadaveric human flexor tendons while preserving mechanical properties and biocompatibility. The purpose of this study is to evaluate the immunogenicity and strength of these grafts when implanted into an immunocompetent rat model. Cadaveric human flexor tendons were divided into two groups. Group 1 was untreated, and Group 2 was decellularized by treatment with sodium dodecyl sulfate (SDS), ethylenediaminetetraacetic acid (EDTA), and peracetic acid (PAA). Both groups were then analyzed for the presence of major histocompatibility complexes by immunohistochemistry (IHC). Pair-matched tendons from each group were then placed into the dorsal subcutaneous tissue and anchored to the spinal ligaments of Wistar rats for 2 or 4 weeks, and harvested. The infiltration of B-cells and macrophages was determined using IHC. The explants where then subjected to mechanical testing to determine the ultimate tensile stress (UTS) and elastic modulus (EM). Statistical analysis was performed using a paired Student's t-test. The decellularization protocol successfully removed cells and MHC-1 complexes. At 2 weeks after implantation, there was increased infiltration of B-cells in Group 1 (untreated) compared with Group 2 (acellular), both in the capsule and tendon substance. There was improved ultimate tensile stress (UTS, 42.7 ± 8.3 vs. 22.8 ± 7.8 MPa, ptendons that were decellularized. At 4 weeks, there was continued B-cell infiltration in Group 1 (untreated) compared with Group 2 (acellular). There was no appreciable difference in macrophage infiltration at both time points. At 4 weeks Group 2 (acellular) demonstrated persistently greater UTS (40.5 ± 9.1 vs. 14.6 ± 4.2 MPa, ptendons that were decellularized with SDS, EDTA, and PAA resulted in removal of cellular antigens and a decreased immune response when placed into Wistar

  4. Biomimetic tendon extracellular matrix composite gradient scaffold enhances ligament-to-bone junction reconstruction.

    Science.gov (United States)

    Liu, Huanhuan; Yang, Long; Zhang, Erchen; Zhang, Rui; Cai, Dandan; Zhu, Shouan; Ran, Jisheng; Bunpetch, Varitsara; Cai, Youzhi; Heng, Boon Chin; Hu, Yejun; Dai, Xuesong; Chen, Xiao; Ouyang, Hongwei

    2017-07-01

    Management of ligament/tendon-to-bone-junction healing remains a formidable challenge in the field of orthopedic medicine to date, due to deficient vascularity and multi-tissue transitional structure of the junction. Numerous strategies have been employed to improve ligament-bone junction healing, including delivery of stem cells, bioactive factors, and synthetic materials, but these methods are often inadequate at recapitulating the complex structure-function relationships at native tissue interfaces. Here, we developed an easily-fabricated and effective biomimetic composite to promote the regeneration of ligament-bone junction by physically modifying the tendon extracellular matrix (ECM) into a Random-Aligned-Random composite using ultrasound treatment. The differentiation potential of rabbit bone marrow stromal cells on the modified ECM were examined in vitro. The results demonstrated that the modified ECM enhanced expression of chondrogenesis and osteogenesis-associated epigenetic genes (Jmjd1c, Kdm6b), transcription factor genes (Sox9, Runx2) and extracellular matrix genes (Col2a1, Ocn), resulting in higher osteoinductivity than the untreated tendon ECM in vitro. In the rabbit anterior cruciate ligament (ACL) reconstruction model in vivo, micro-computed tomography (Micro-CT) and histological analysis showed that the modified Random-Aligned-Random composite scaffold enhanced bone and fibrocartilage formation at the interface, more efficaciously than the unmodified tendon ECM. Therefore, these results demonstrated that the biomimetic Random-Aligned-Random composite could be a promising scaffold for ligament/tendon-bone junction repair. The native transitional region consists of several distinct yet contiguous tissue regions, composed of soft tissue, non-calcified fibrocartilage, calcified fibrocartilage, and bone. A stratified graft whose phases are interconnected with each other is essential for supporting the formation of functionally continuous multi

  5. Minimally invasive reconstruction of chronic achilles tendon ruptures using the ipsilateral free semitendinosus tendon graft and interference screw fixation.

    Science.gov (United States)

    Maffulli, Nicola; Loppini, Mattia; Longo, Umile Giuseppe; Maffulli, Gayle D; Denaro, Vincenzo

    2013-05-01

    Achilles tendon ruptures represent more than 40% of all tendon ruptures requiring surgical management. About 20% of acute Achilles tendon tears are not diagnosed at the time of injury and become chronic, necessitating more complicated management than fresh injuries. Several techniques for the reconstruction of chronic tears of the Achilles tendon have been described, but the superiority of one technique over the others has not been demonstrated. Mini-invasive reconstruction of the Achilles tendon, with a gap lesion larger than 6 cm, using the ipsilateral free semitendinosus tendon graft will result in improvement of the overall function with a low rate of complications. Case series; Level of evidence, 4. Between 2008 and 2010, the authors prospectively enrolled 28 consecutive patients (21 men and 7 women; median age, 46 years) with chronic closed ruptures of the Achilles tendon who had undergone reconstruction with a free semitendinosus tendon graft. They assessed the Achilles tendon Total Rupture Score (ATRS), maximum calf circumference, and isometric plantarflexion strength before surgery and at the last follow-up. Outcome of surgery and rate of complications were also recorded. The median follow-up after surgery was 31.4 months. The overall result of surgery was excellent/good in 26 (93%) of 28 patients. The ATRS improved from 42 (range, 29-55) to 86 (range, 78-95) (P tendon, with a gap lesion larger than 6 cm, using the ipsilateral free semitendinosus tendon graft provides a significant improvement of symptoms and function, although calf circumference and ankle plantarflexion strength do not recover fully.

  6. A magnetic resonance imaging study of abnormalities of the patella and patellar tendon that predispose children to acute patellofemoral dislocation.

    Science.gov (United States)

    Yılmaz, Barış; Çiçek, Esin Derin; Şirin, Evrim; Özdemir, Güzelali; Karakuş, Özgün; Muratlı, Hasan Hilmi

    This study compared 20 children hospitalised with acute patellofemoral dislocation with an age-matched healthy control group with no history of knee problems or patellar dislocation. The following morphological parameters were significantly different between the groups: the mean patellar width and length, mean sulcus depth, mean patellar tendon width and total patellar volume. The magnetic resonance imaging findings of this study suggested that structurally smaller than normal patella and patellar tendon volumes are predisposing factors for acute patellofemoral dislocation. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Bilateral simultaneous spontaneous rupture of the quadriceps tendons

    African Journals Online (AJOL)

    simultaneous rupture of the quadriceps tendons. The injury occurs most often in elderly people and delay in the diagnosis is not uncommon. Early operative repair is recommended. By using a metal wire passing through a transverse hole in the superior pole of the patella and through the tendon proximal to the repair site, ...

  8. Rehabilitation of tendon problems in patients with diabetes mellitus

    NARCIS (Netherlands)

    Rees, Jonathan; Gaida, Jamie E.; Silbernagel, Karin Grävare; Zwerver, Johannes; Anthony, Joseph S.; Scott, Alex; Ackermann, PW; Hart, DA

    2016-01-01

    Exercise is crucial in the management of diabetes mellitus and its associated complications. However, individuals with diabetes have a heightened risk of musculoskeletal problems, including tendon pathologies. Diabetes has a significant impact on the function of tendons due to the accumulation of

  9. Intratendinous Ganglion of the Extensor Tendon of the Hand.

    Science.gov (United States)

    Lee, Hyun-Joo; Kim, Poong-Taek; Chang, Hyo-Won

    2015-01-01

    Ganglion is a common benign lesion that usually arises adjacent to the joints or tendons of the hand. However, an intratendinous ganglion is a rare condition. We report two cases of intratendinous ganglion of the extensor tendon of the hand which were treated with excision.

  10. Surgical management of acute quadriceps tendon rupture (a case ...

    African Journals Online (AJOL)

    Surgical repair is realized in emergency to completely restore the extension. We report a case of a patient who has sustained of complete quadriceps tendon tear after a long period of tendon weakening by statin therapy, hypertension and diabetes. The repair has consisted on end-to-end Krackow sutures associated with ...

  11. Reliability of the clinical and electromyographic examination of tendon reflexes

    NARCIS (Netherlands)

    Stam, J.; van Crevel, H.

    1990-01-01

    The reliability of clinical examination of the tendon reflexes was examined by studying inter-observer agreement. Twenty patients were examined by three neurologists. The briskness of the tendon reflexes in arms and legs was scored on a nine-point scale. In 28% of the 160 examined reflexes the

  12. Avulsion of subscapularis muscle tendon leading to recurrent ...

    African Journals Online (AJOL)

    Key words: sho~~lder, recurrent dislocation, subscapularis tendon avulsion. Fifteen patients, ten ... The dislocation was found to be due to a complete tear of the subscapularis tendon (12 patients) and partial tears in three patients, without fracture of the lesser tuberosity ... Exercises to strengthen the internal rotator muscles ...

  13. Tendon needling for treatment of tendinopathy: A systematic review.

    Science.gov (United States)

    Krey, David; Borchers, James; McCamey, Kendra

    2015-02-01

    To summarize the best available evidence to determine if tendon needling is an effective treatment for tendinopathy. Data source. Medline and Cochrane Databases through November 2013. Utilizing the search terms tendinopathy, needle, needling, tenotomy, dry needling, needling tendon, needle fenestration, and tendon fenestration, 17 articles were identified through our systematic literature search. Of these, 4 studies met the inclusion criteria. Four independent reviewers reviewed the articles. The study results and generated conclusions were agreed upon. The studies that were included in this review suggest that tendon needling improves patient reported outcomes in patients with tendinopathy. In 2 studies evaluating tendon needling in lateral epicondylosis, one showed an improvement in a subjective visual analogue scale score of 34% (significant change > 25%) from baseline at 6 months. The other showed an improvement of 56.1% in a visual analogue scale score from baseline. In 1 study evaluating tendon needling in addition to eccentric therapy for Achilles tendinosis, the subjective Victorian Institute of Sport Assessment-Achilles (VISA-A) score improved by 19.9 (significant change > 10) (95% CI, 13.6-26.2) from baseline. In 1 study evaluating tendon needling in rotator cuff tendinosis, the subjective shoulder pain and disability index showed statistical significant improvement from baseline at 6 months (P < 0.05). The evidence suggests that tendon needling improves patient-reported outcome measures in patients with tendinopathy. There is a trend that shows that the addition of autologous blood products may further improve theses outcomes.

  14. Case Report:Triceps Tendon Avulsion: A Rare Injury | Sharma ...

    African Journals Online (AJOL)

    Background: Triceps tendon avulsion is one of the rare tendinous injuries. Such injuries can easily be missed, and should be kept as a differential diagnosis in all patients who present with pain and swelling at the back of the elbow after a traumatic event. Case Details: We present a case of triceps tendon avulsion which ...

  15. Rare causes of closed rupture of the flexor tendon

    NARCIS (Netherlands)

    Stenekes, Martin W.; Ruttermann, Mike; Werker, Paul M. N.

    Closed injuries to the flexor tendon are relatively rare. We present three rare causes of closed injury to the flexor tendon. Early recognition and adequate treatment by a specialised hand surgeon are crucial for the prognosis of such cases. Delayed diagnosis and treatment often require secondary

  16. Development of Mechanical Anchor for CFRP Tendons Using Integrated Sleeve

    DEFF Research Database (Denmark)

    Schmidt, Jacob Wittrup; Bennitz, Anders; Täljsten, Björn

    2010-01-01

    A durable and very efficient external strengthening system is achieved if steel tendons for post-tensioning applications can be replaced with CFRP (Carbon Fibre Reinforced Polymer) tendons and if reliable anchorage systems are developed,. This paper presents a newly developed and simple-to-use tw...

  17. Closed rupture of the thumb flexor tendon pulleys.

    Science.gov (United States)

    Wilson, S M; Roulot, E; Le Viet, D

    2005-12-01

    Closed flexor tendon pulley ruptures are relatively rare injuries. All previously reported cases have been in the long finger pulleys. To our knowledge, there has not been a case of closed thumb flexor tendon pulley rupture reported in the literature. This paper presents two cases of this pathology and discusses appropriate treatment of it.

  18. Tendon Cell Behavior and Matrix Remodeling in Degenerative Tendinopathy

    NARCIS (Netherlands)

    M. de Mos (Marieke)

    2009-01-01

    textabstractTendon injuries are common in human athletes [1-4]. Furthermore, such injuries are also prevalent in the ageing sedentary population [5-7]. In recent decades, the incidence of tendon injuries has risen due to both an increase in an elderly population and a rise in participation

  19. Painful snapping hip owing to bifid iliopsoas tendon and concurrent ...

    African Journals Online (AJOL)

    2015-05-22

    May 22, 2015 ... A case of internal snapping hip owing to a bifid iliopsoas tendon is described with a concurrent labral tear in a young active female. The labral tear was identified on magnetic resonance imaging, and the snapping bifid tendon on dynamic ultrasound. The patient was administered bupivicaine and steroid ...

  20. Surgical Strategy for the Chronic Achilles Tendon Rupture

    Directory of Open Access Journals (Sweden)

    Yangjing Lin

    2016-01-01

    Full Text Available Background. Chronic Achilles tendon rupture is usually misdiagnosed and treated improperly. This study aims to better understand the treatment of chronic Achilles tendon rupture. Methods. Patients who were not able to perform a single-limb heel rise were chosen. Pre- and postoperative magnetic resonance imaging (MRI were conducted. By evaluating the presence or absence of Achilles tendon stumps and the gap length of rupture, V-Y advancement, gastrocnemius fascial turndown flap, or flexor halluces longus tendon transfer were selected for tendon repair. The function of ankle and foot was assessed by American Orthopaedic Foot & Ankle Society (AOFAS ankle-hindfoot scores and Achilles Tendon Total Rupture Score (ATRS. Results. Twenty-nine patients were followed up. One patient had superficial incision infection, which was healed after debridement and oral antibiotics. Three months postoperatively, MRI showed some signs of inflammation, which disappeared at one or two years postoperatively. All patients were able to perform a single-limb heel rise. Mean AOFAS scores and ATRS scores were increased at the latest follow-up. Conclusion. Surgical options can be determined by evaluating the presence of the Achilles tendon stumps and the gap length, which can avoid using the nearby tendon and yield satisfactory functional results.

  1. Surgical Strategy for the Chronic Achilles Tendon Rupture

    Science.gov (United States)

    Yang, Liu; Yin, Li

    2016-01-01

    Background. Chronic Achilles tendon rupture is usually misdiagnosed and treated improperly. This study aims to better understand the treatment of chronic Achilles tendon rupture. Methods. Patients who were not able to perform a single-limb heel rise were chosen. Pre- and postoperative magnetic resonance imaging (MRI) were conducted. By evaluating the presence or absence of Achilles tendon stumps and the gap length of rupture, V-Y advancement, gastrocnemius fascial turndown flap, or flexor halluces longus tendon transfer were selected for tendon repair. The function of ankle and foot was assessed by American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scores and Achilles Tendon Total Rupture Score (ATRS). Results. Twenty-nine patients were followed up. One patient had superficial incision infection, which was healed after debridement and oral antibiotics. Three months postoperatively, MRI showed some signs of inflammation, which disappeared at one or two years postoperatively. All patients were able to perform a single-limb heel rise. Mean AOFAS scores and ATRS scores were increased at the latest follow-up. Conclusion. Surgical options can be determined by evaluating the presence of the Achilles tendon stumps and the gap length, which can avoid using the nearby tendon and yield satisfactory functional results. PMID:27847806

  2. Botulinum Neurotoxin A injections influence stretching of the gastrocnemius muscle-tendon unit in an animal model.

    Science.gov (United States)

    Haubruck, Patrick; Mannava, Sandeep; Plate, Johannes F; Callahan, Michael F; Wiggins, Walter F; Schmidmaier, Gerhard; Tuohy, Christopher J; Saul, Katherine R; Smith, Thomas L

    2012-08-01

    Botulinum Neurotoxin A (BoNT-A) injections have been used for the treatment of muscle contractures and spasticity. This study assessed the influence of (BoNT-A) injections on passive biomechanical properties of the muscle-tendon unit. Mousegastrocnemius muscle (GC) was injected with BoNT-A (n = 18) or normal saline (n = 18) and passive, non-destructive, in vivo load relaxation experimentation was performed to examine how the muscle-tendon unit behaves after chemical denervation with BoNT-A. Injection of BoNT-A impaired passive muscle recovery (15% vs. 35% recovery to pre-stretching baseline, p stretch reflex; thereby modulating in vivo passive muscle properties. However, it is also possible that BoNT-A injection may alter the structure of skeletal muscle; thus modulating the in vivo passive biomechanical properties of the muscle-tendon unit.

  3. Pain level after ACL reconstruction: A comparative study between free quadriceps tendon and hamstring tendons autografts.

    Science.gov (United States)

    Buescu, Cristian Tudor; Onutu, Adela Hilda; Lucaciu, Dan Osvald; Todor, Adrian

    2017-03-01

    The objective of this study was to compare the pain levels and analgesic consumption after single bundle ACL reconstruction with free quadriceps tendon autograft versus hamstring tendon autograft. A total of 48 patients scheduled for anatomic single-bundle ACL reconstruction were randomized into two groups: the free quadriceps tendon autograft group (24 patients) and the hamstring tendons autograft group (24 patients). A basic multimodal analgesic postoperative program was used for all patients and rescue analgesia was provided with tramadol, at pain scores over 30 on the Visual Analog Scale. The time to the first rescue analgesic, the number of doses of tramadol and pain scores were recorded. The results within the same group were compared with the Wilcoxon signed test. Supplementary analgesic drug administration proved significantly higher in the group of subjects with hamstring grafts, with a median (interquartile range) of 1 (1.3) dose, compared to the group of subjects treated with a quadriceps graft, median = 0.5 (0.1.25) (p = 0.009). A significantly higher number of subjects with a quadriceps graft did not require any supplementary analgesic drug (50%) as compared with subjects with hamstring graft (13%; Z-statistics = 3.01, p = 0.002). The percentage of subjects who required a supplementary analgesic drug was 38% higher in the HT group compared with the FQT group. The use of the free quadriceps tendon autograft for ACL reconstruction leads to less pain and analgesic consumption in the immediate postoperative period compared with the use of hamstrings autograft. Level I Therapeutic study. Copyright © 2017 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

  4. Do Dietary Factors Influence Tendon Metabolism?

    Science.gov (United States)

    Scott, Alex; Nordin, Cara

    There is very little direct research to conclusively prove the relevance of diet in primary tendinopathies, however it seems prudent to ask whether our current knowledge about the impact of nutrition on collagen metabolism could be useful in assessing, preventing, or treating tendinopathy. The objective of this chapter is to discuss the potential impact (negative or positive) that nutrition may have on the metabolism of tendons by summarizing the related research. The chapter briefly discusses the roles that specific vitamins, amino acids, lipids, and antioxidants have in various processes of the body that may be directly or indirectly related to tenocyte metabolism.

  5. Achilles tendon rupture; assessment of nonoperative treatment

    DEFF Research Database (Denmark)

    Barfod, Kristoffer Weisskirchner

    2014-01-01

    to be clarified, particularly the role of weight-bearing during early rehabilitation. Also, there is a need for a clinically applicable and accurate measurement to detect patients in risk of developing Achilles tendon elongation. PURPOSE: The aim of this PhD thesis was to evaluate non-operative treatment of acute...... I found surgery to be the preferred treatment in 83% of departments in Denmark, 92% in Norway, 65% in Sweden, and 30% in Finland (p up except from a better health......-related quality of life in the weight-bearing group (p=0.009). Compared to the unaffected limb, the affected limb had decreased stiffness (77%, p

  6. Nonoperative, dynamic treatment of acute achilles tendon rupture

    DEFF Research Database (Denmark)

    Barfod, Kristoffer Weisskirchner; Bencke, Jesper; Lauridsen, Hanne Bloch

    2015-01-01

    ° dorsiflexion, the stiffness during slow stretching, and the maximal strength were measured in both limbs. The stiffness of the plantar flexor muscle-tendon complex in the terminal part of dorsiflexion was significantly increased (p = .024) in the non-weightbearing group at 12 months. The peak passive torque......Acute Achilles tendon rupture alters the biomechanical properties of the plantar flexor muscle-tendon complex that can affect functional performance and the risk of repeat injury. The purpose of the present study was to compare the biomechanical properties of the plantar flexor muscle......-tendon complex in patients randomized to early weightbearing or non-weightbearing in the nonoperative treatment of Achilles tendon rupture. A total of 60 patients were randomized to full weightbearing from day 1 of treatment or non-weightbearing for 6 weeks. After 6 and 12 months, the peak passive torque at 20...

  7. Fibroma of the flexor hallucis longus tendon sheath.

    Science.gov (United States)

    Kim, Sang Wha; Lee, So Young; Jung, Sung-No; Sohn, Won Il; Kwon, Ho

    2012-01-01

    Fibroma of tendon sheath is a rare benign tumor that usually occurs in upper extremities. It is mostly asymptomatic and grows slowly within the tendons or tendon sheaths. Histopathologic findings show well-demarcated nodules consisting of haphazardly arranged fibroblast-like spindle cells, which are embedded in a dense, collagenous matrix. We present a patient with fibroma of the tendon sheath on the flexor hallucis longus tendon, which was in an unusual location and has never been reported. The lesion was completely excised and showed no evidence of recurrence after 2 years of follow-up. Copyright © 2012 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  8. Use of fluroquinolone and risk of Achilles tendon rupture

    DEFF Research Database (Denmark)

    Sode, Jacob; Obel, Niels; Hallas, Jesper

    2007-01-01

    OBJECTIVE: Several case-control studies have reported that the use of fluoroquinolone increases the risk of rupture of the Achilles tendon. Our aim was to estimate this risk by means of a population-based cohort approach. SETTING: Data on Achilles tendon ruptures and fluoroquinolone use were...... retrieved from three population-based databases that include information on residents of Funen County (population: 470,000) in primary and secondary care during the period 1991-1999. A study cohort of all 28,262 first-time users of fluoroquinolone and all incident cases of Achilles tendon ruptures were...... identified. MAIN OUTCOME MEASURES: The incidence rate of Achilles tendon ruptures among users and non-users of fluoroquinolones and the standardised incidence rate ratio associating fluoroquinolon use with Achilles tendon rupture were the main outcome measures. RESULTS: Between 1991 and 2002 the incidence...

  9. System and Method for Tensioning a Robotically Actuated Tendon

    Science.gov (United States)

    Reiland, Matthew J. (Inventor); Diftler, Myron A. (Inventor)

    2013-01-01

    A tendon tensioning system includes a tendon having a proximal end and a distal end, an actuator, and a motor controller. The actuator may include a drive screw and a motor, and may be coupled with the proximal end of the tendon and configured to apply a tension through the tendon in response to an electrical current. The motor controller may be electrically coupled with the actuator, and configured to provide an electrical current having a first amplitude to the actuator until a stall tension is achieved through the tendon; provide a pulse current to the actuator following the achievement of the stall tension, where the amplitude of the pulse current is greater than the first amplitude, and return the motor to a steady state holding current following the conclusion of the pulse current.

  10. Ossification of the Achilles tendon: imaging abnormalities in 12 patients

    Energy Technology Data Exchange (ETDEWEB)

    Yu, J.S. [Dept. of Radiology, Veterans Administration Medical Center, San Diego, CA (United States); Witte, D. [Dept. of Radiology, Veterans Administration Medical Center, San Diego, CA (United States); Resnick, D. [Dept. of Radiology, Veterans Administration Medical Center, San Diego, CA (United States); Pogue, W. [Dept. of Radiology, AMI Valley Medical Center, El Cajon, CA (United States)

    1994-02-01

    Ossification of the Achilles tendon is a rare clinical entity that is characterized by the presence of an ossific mass contained within the fibrocartilaginous substance of the tendon. Because the radiographic features of this condition have not been documented entirely and the magnetic resonance (MR) imaging findings have not been determined, a review of 16 affected tendons in 12 patients was performed in an attempt to characterize the imaging abnormalities associated with this process. MR imaging was performed in three Achilles tendons which demonstrated thickening of the tendons at the level of the ossifications and a lack of intratendinous signal abnormalities compatible with acute tendinitis. Signal intensity similar to that of bone marrow was present in the ossifications. (orig.)

  11. Patellar tendon ossification after partial patellectomy: a case report

    Directory of Open Access Journals (Sweden)

    Guven Melih

    2010-02-01

    Full Text Available Abstract Introduction Patellar tendon ossification is a rare pathology that may be seen as a complication after sleeve fractures of the tibial tuberosity, total patellectomy during arthroplasty, intramedullary nailing of tibial fractures, anterior cruciate ligament reconstruction with patellar tendon autograft and knee injury without fracture. However, its occurrence after partial patellectomy surgery has never been reported in the literature. Case presentation We present the case of a 35-year-old Turkish man with a comminuted inferior patellar pole fracture that was treated with partial patellectomy. During the follow-up period, his patellar tendon healed with ossification and then ruptured from the inferior attachment to the tibial tubercle. The ossification was excised and the tendon was subsequently repaired. Conclusion To the best of our knowledge, this is the first report of patellar tendon ossification occurring after partial patellectomy. Orthopaedic surgeons are thus cautioned to be conscious of this rare complication after partial patellectomy.

  12. Validation of a novel ultrasound measurement of achilles tendon length

    DEFF Research Database (Denmark)

    Barfod, Kristoffer Weisskirchner; Riecke, Anja Falk; Boesen, Anders

    2014-01-01

    PURPOSE: A clinically applicable and accurate method for measuring Achilles tendon length is needed to investigate the influence of elongation of the Achilles tendon after acute rupture. The purpose of this study was to develop and validate an ultrasonographic (US) length measurement...... of the Achilles tendon-aponeurosis complex. METHODS: Both legs of 19 non-injured subjects were examined by magnetic resonance imaging (MRI) and US. The length from calcaneus to the medial head of m. Gastrocnemius was measured by three independent US examiners. Repeated US measurements were performed and compared...... to be further assessed in the setting of acute Achilles tendon rupture. CLINICAL RELEVANCE: This new ultrasound measurement might allow for length measurement of ruptured Achilles tendons in the acute and chronic state after rupture. LEVEL OF EVIDENCE: II....

  13. Muscle-tendon glucose uptake in Achilles tendon rupture and tendinopathy before and after eccentric rehabilitation: Comparative case reports.

    Science.gov (United States)

    Masood, Tahir; Kalliokoski, Kari; Bojsen-Møller, Jens; Finni, Taija

    2016-09-01

    Achilles tendon rupture (ATR) is the most common tendon rupture injury. The consequences of ATR on metabolic activity of the Achilles tendon and ankle plantarflexors are unknown. Furthermore, the effects of eccentric rehabilitation on metabolic activity patterns of Achilles tendon and ankle plantarflexors in ATR patients have not been reported thus far. We present a case study demonstrating glucose uptake (GU) in the Achilles tendon, the triceps surae, and the flexor hallucis longus of a post-surgical ATR patient before and after a 5-month eccentric rehabilitation. At baseline, three months post-surgery, all muscles and Achilles tendon displayed much higher GU in the ATR patient compared to a healthy individual despite lower plantarflexion force. After the rehabilitation, plantarflexion force increased in the operated leg while muscle GU was considerably reduced. The triceps surae muscles showed similar values to the healthy control. When compared to the healthy or a matched patient with Achilles tendon pain after 12 weeks of rehabilitation, Achilles tendon GU levels of ATR patient remained greater after the rehabilitation. Past studies have shown a shift in the metabolic fuel utilization towards glycolysis due to immobilization. Further research, combined with immuno-histological investigation, is needed to fully understand the mechanism behind excessive glucose uptake in ATR cases. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Quadriceps Tendon Rupture and Contralateral Patella Tendon Avulsion Post Primary Bilateral Total Knee Arthroplasty: A Case Report

    Directory of Open Access Journals (Sweden)

    Gaurav Sharma

    2016-07-01

    Full Text Available Background: Extensor mechanism failure secondary to knee replacement could be due to tibial tubercle avulsion, Patellar tendon rupture, patellar fracture or quadriceps tendon rupture. An incidence of Patella tendon rupture of 0.17% and Quadriceps tendon rupture of around 0.1% has been reported after Total knee arthroplasty. These are considered a devastating complication that substantially affects the clinical results and are challenging situations to treat with surgery being the mainstay of the treatment. Case Description: We report here an interesting case of a patellar tendon rupture of one knee and Quadriceps tendon rupture of the contralateral knee following simultaneous bilateral knee replacement in a case of inflammatory arthritis patient. End to end repair for Quadriceps tear and augmentation with Autologous Hamstring tendon graft was done for Patella tendon rupture. OUTCOME: Patient was followed up for a period of 1 year and there was no Extension lag with a flexion of 100 degrees in both the knees. DISCUSSION: The key learning points and important aspects of diagnosing these injuries early and the management techniques are described in this unique case of bilateral extensor mechanism disruption following knee replacements.

  15. Combined flexor hallucis longus tendon transfer and gastrocnemius recession for reconstruction of gapped chronic achilles tendon ruptures.

    Science.gov (United States)

    Elgohary, Hatem Elsayed Ahmed; Elmoghazy, Nabil A; Abd Ellatif, Mohammed Serry

    2016-12-01

    The aim of this study was to assess the functional outcomes after a combined FHL transfer and a gastrocnemius recession for treatment of chronic ruptures of Achilles tendon with a gap and to investigate the patient's satisfaction about the great toe function after transfer. 19 patients with chronic rupture of the Achilles tendon with a gap were treated with a flexor halluces longus tendon transfer combined with a gastrocnemius recession, Clinical diagnosis depends on the presence of gap in the tendon on examination, inability of tip toe walking on the affected side and positive calf-squeeze test, MRI was used to confirm the clinical diagnosis. American Orthopedic Foot & Ankle Society hind foot score was used for assessment of the results. The AOFAS score improved significantly from a mean of 65 preoperatively to 94 at the last follow up (ptendon weaved through the stump of the Achilles tendon and those with trans osseous tunnels, the mean AOFAS score at the last follow up was 94.2, 93.8 respectively, no patient complained of big toe dysfunction. Management of chronic rupture of the Achilles tendon with a gap with flexor halluces longus tendon transfer combined with a gastrocnemius recession is a safe and reliable method with a significantly improved functional outcome, muscle advancement through gastrocnemius recession decreases the length of the gap without affecting the muscle function, flexor halluces longus tendon transfer doesn't harm the big toe function. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Endoscopic-assisted achilles tendon reconstruction with free hamstring tendon autograft for chronic rupture of achilles tendon: clinical and isokinetic evaluation.

    Science.gov (United States)

    El Shazly, Ossama; Abou El Soud, Maged M; El Mikkawy, Dalia M E; El Ganzoury, Ibrahim; Ibrahim, Ayman Mohamed

    2014-05-01

    To evaluate the clinical and functional outcome of endoscopic-assisted reconstruction of chronic ruptures of the Achilles tendon using free hamstring tendon autograft. We present a case series of 15 patients who had chronic ruptures of the Achilles tendon (>6 weeks earlier) and underwent endoscopic-assisted reconstruction with a free hamstring autograft. The graft loop was passed through and fixed to the proximal stump of the tendon. The graft was then passed through suture to the distal stump and finally inserted into a tunnel in the anterior calcaneus to the Achilles tendon insertion and fixed with an bioabsorbable interference screw. The mean follow-up period was 27 months (SD, 3 months; range, 24 to 33 months). All patients underwent magnetic resonance imaging preoperatively, immediately postoperatively, and at follow-up 2 years postoperatively. All patients were functionally evaluated with the American Orthopaedic Foot & Ankle Society (AOFAS) score for the hindfoot preoperatively and postoperatively. Calf muscle power was evaluated by isokinetic strength testing at 2 years' follow-up. The mean size of the gap on preoperative magnetic resonance imaging was 49 mm (SD, 9 mm). The mean preoperative AOFAS score was 32.6 (SD, 7.5). There was a statistically significant improvement in the postoperative AOFAS score after 2 years to 90.8 (SD, 3.54) (P Achilles tendon reconstruction with free hamstring tendon autograft for chronic ruptures of the Achilles tendon showed good to excellent results in all patients. Isokinetic testing showed a nonsignificant deficit between the involved and uninvolved sides at 2 years' follow-up. Level IV, therapeutic cases series. Copyright © 2014 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  17. Surgical Treatment for Failure of Repair of Patellar and Quadriceps Tendon Rupture With Ipsilateral Hamstring Tendon Graft.

    Science.gov (United States)

    Maffulli, Nicola; Papalia, Rocco; Torre, Guglielmo; Denaro, Vincenzo

    2017-03-01

    Tears of the patellar and quadriceps tendon are common in the active population, especially in athletes. At present, several techniques for surgical repair and reconstruction are available. When reruptures occur, a reconstruction is mandatory. In the present paper, we describe a surgical technique for patellar and quadriceps tendon reconstruction using ipsilateral hamstring autograft. After routine hamstring tendon harvesting, the tendon ends are prepared using a whip stitch. A transverse tunnel is drilled in the midportion of the patella, the hamstring graft is passed through the patella, and firmly secured to the patellar tunnel openings with sutures. The details of the technique are fully described. Autologous ipsilateral hamstring tendon grafts provide a secure sound means to manage these challenging injuries.

  18. Tissue engineering of flexor tendons: the effect of a tissue bioreactor on adipoderived stem cell-seeded and fibroblast-seeded tendon constructs.

    Science.gov (United States)

    Angelidis, Ioannis K; Thorfinn, Johan; Connolly, Ian D; Lindsey, Derek; Pham, Hung M; Chang, James

    2010-09-01

    Tissue-engineered flexor tendons could eventually be used for reconstruction of large tendon defects. The goal of this project was to examine the effect of a tissue bioreactor on the biomechanical properties of tendon constructs seeded with adipoderived stem cells (ASCs) and fibroblasts (Fs). Rabbit rear paw flexor tendons were acellularized and seeded with ASCs or Fs. A custom bioreactor applied a cyclic mechanical load of 1.25 N at 1 cycle/minute for 5 days onto the tendon constructs. Three additional groups were used as controls: fresh tendons and tendons reseeded with either ASCs or Fs that were not exposed to the bioreactor treatment and were left in stationary incubation for 5 days. We compared the ultimate tensile stress (UTS) and elastic modulus (EM) of bioreactor-treated tendons with the unloaded control tendons and fresh tendons. Comparison across groups was assessed using one-way analysis of variance with the significance level set at ptendons that were exposed to cyclic load were significantly higher than those of unloaded control tendons. Acellularized tendon constructs that were reseeded with ASCs and exposed to a cyclic load had a UTS of 66.76 MPa and an EM of 906.68 MPa; their unloaded equivalents had a UTS of 47.90 MPa and an EM of 715.57 MPa. Similar trends were found in the fibroblast-seeded tendon constructs that were exposed to the bioreactor treatment. The bioreactor-treated tendons approached the UTS and EM values of fresh tendons. Histologically, we found that cells reoriented themselves parallel to the direction of strain in response to cyclic strain. The application of cyclic strain on seeded tendon constructs that were treated with the bioreactor helped achieve a UTS and an EM comparable with those of fresh tendons. Bioreactor pretreatment and alternative cell lines, such as ASCs and Fs, might therefore contribute to the in vitro production of strong tendon material. Copyright 2010. Published by Elsevier Inc.

  19. Ruptures of the distal biceps tendon.

    Science.gov (United States)

    Ward, James P; Shreve, Mark C; Youm, Thomas; Strauss, Eric J

    2014-01-01

    Distal biceps ruptures occur most commonly in middle-aged males and result from eccentric contraction of the biceps tendon. The injury typically presents with pain and a tearing sensation in the antecubital fossa with resultant weakness in flexion and supination strength. Physical exam maneuvers and diagnostic imaging aid in determining the diagnosis. Nonoperative management is reserved for elderly, low demand patients, while operative intervention is generally pursued for younger patients and can consist of nonanatomic repair to the brachialis or anatomic repair to the radial tuberosity. Anatomic repair through a one-incision or two-incision approach is commonplace, while the nonanatomic repairs are rarely performed. No clear advantage exists in operative management with a one-incision versus two-incision techniques. Chronic ruptures present a more difficult situation, and allograft augmentation is often necessary. Common complications after repair include transient nerve palsy, which often resolves, and heterotopic ossification. Despite these possible complications, most studies suggest that better patient outcomes are obtained with operative, anatomic reattachment of the distal biceps tendon.

  20. The Effect of Sodium Hyaluronate on Ligamentation and Biomechanical Property of Tendon in Repair of Achilles Tendon Defect with Polyethylene Terephthalate Artificial Ligament: A Rabbit Tendon Repair Model

    Directory of Open Access Journals (Sweden)

    Shengkun Li

    2016-01-01

    Full Text Available The Achilles tendon is the most common ruptured tendon of human body. Reconstruction with polyethylene terephthalate (PET artificial ligament is recommended in some serious cases. Sodium hyaluronate (HA is beneficial for the healing of tendon injuries. We aimed to determine the effect of sodium hyaluronate in repair of Achilles tendon defect with PET artificial ligament in an animal tendon repair model. Sixteen New Zealand White rabbits were divided into two groups. Eight rabbits repaired with PET were assigned to PET group; the other eight rabbits repaired with PET along with injection of HE were assigned to HA-PET group. All rabbits were sacrificed at 4 and 8 weeks postoperatively for biomechanical and histological examination. The HA-PET group revealed higher biomechanical property compared with the PET group. Histologically, more collagen tissues grew into the HA-PET group compared with PET group. In conclusion, application of sodium hyaluronate can improve the healing of Achilles tendon reconstruction with polyethylene terephthalate artificial ligament.

  1. Fetal development of the pulley for muscle insertion tendons: A review and new findings related to the tensor tympani tendon.

    Science.gov (United States)

    Rodríguez-Vázquez, Jose Francisco; Honkura, Yohei; Katori, Yukio; Murakami, Gen; Abe, Hiroshi

    2017-01-01

    The existence of hard tissue pulleys that act to change the direction of a muscle insertion tendon is well known in the human body. These include (1) the trochlea for the extraocular obliquus superior muscle, (2) the pterygoid hamulus for the tensor veli palatini muscle, (3) the deep sulcus on the plantar aspect of the cuboid bone for the peroneus longus tendon, (4) the lesser sciatic notch for the obturator internus muscle, and (5) the bony trochleariformis process for the tensor tympani muscle tendon. In addition, (6) the stapedius muscle tendon shows a lesser or greater angulation at the pyramidal eminence of the temporal bone. Our recent studies have shown that the development of pulleys Nos. 1 and 2 can be explained by a change in the topographical relationship between the pulley and the tendon, that of pulley No. 3 by the rapidly growing calcaneus pushing the tendon, and that of pulley No. 4 by migration of the insertion along the sciatic nerve and gluteus medius tendon. Therefore, in Nos. 1-4, an initially direct tendon curves secondarily and obtains an attachment to the pulley. In case No. 6, the terminal part of the stapedius tendon originates secondarily from the interzone mesenchymal tissue of the incudostapedial joint. In the case of pulley No. 5, we newly demonstrated that its initial phase of development was similar to No. 6, but the tensor tympani tendon achieved a right-angled turn under guidance by a specific fibrous tissue and it migrated along the growing malleus manubrium. Copyright © 2016 Elsevier GmbH. All rights reserved.

  2. Influence of neglecting the curved path of the Achilles tendon on Achilles tendon length change at various ranges of motion

    Science.gov (United States)

    Fukutani, Atsuki; Hashizume, Satoru; Kusumoto, Kazuki; Kurihara, Toshiyuki

    2014-01-01

    Abstract Achilles tendon length has been measured using a straight‐line model. However, this model is associated with a greater measurement error compared with a curved‐line model. Therefore, we examined the influence of neglecting the curved path of the Achilles tendon on its length change at various ranges of motion. Ten male subjects participated in this study. First, the location of the Achilles tendon was confirmed by using ultrasonography, and markers were attached on the skin over the Achilles tendon path. Then, the three‐dimensional coordinates of each marker at dorsiflexion (DF) 15°, plantarflexion (PF) 0°, PF15°, and PF30° were obtained. Achilles tendon length in the curved‐line model was calculated as the sum of the distances among each marker. On the other hand, Achilles tendon length in the straight‐line model was calculated as the straight distance between the two most proximal and distal markers projected onto the sagittal plane. The difference of the Achilles tendon length change between curved‐line and straight‐line models was calculated by subtracting the Achilles tendon length change obtained in curved‐line model from that obtained in straight‐line model with three different ranges of motion (i.e., PF0°, PF15°, and PF30° from DF15°, respectively). As a result, the difference in Achilles tendon length change between the two models increased significantly as the range of motion increased. In conclusion, neglecting the curved path of the Achilles tendon induces substantial overestimation of its length change when the extent of ankle joint angle change is large. PMID:25303951

  3. Dynamic adaptation of tendon and muscle connective tissue to mechanical loading

    DEFF Research Database (Denmark)

    Mackey, Abigail; Heinemeier, Katja Maria; Koskinen, Satu Osmi Anneli

    2008-01-01

    The connective tissue of tendon and skeletal muscle is a crucial structure for force transmission. A dynamic adaptive capacity of these tissues in healthy individuals is evident from reports of altered gene expression and protein levels of the fibrillar and network-forming collagens, when subjected...... in this article provide strong evidence for the highly adaptable nature of connective tissue in muscle and tendon......., in particular TGF-beta-1, and matrix remodelling enzymes such as MMP-2. Furthermore, it is under hormonal influence. In skeletal muscle, the extracellular matrix demonstrates its potential for cross-talk by regulating the activity of cells with which it is in contact. Taken together, the studies highlighted...

  4. Calcinosis Circumscripta in the Digital Extensor Tendon of a Tawny Eagle (Aquila rapax).

    Science.gov (United States)

    Sabater, Mikel; Carrasco, Daniel Calvo; Huynh, Minh; Homer-Forbes, Neil A; Stidworthy, Mark F

    2016-12-01

    A 9-month-old, captive-bred, female tawny eagle (Aquila rapax) presented with a nonpainful, firm, nodular structure attached to the digital extensor tendon. The mass was surgically resected without complications and was submitted for histopathologic examination. Grossly, cut surfaces of the lesion had chalky-white deposits. Histologically, the resected tissue was identified as calcinosis circumscripta. No recurrence was observed in follow-up after 6 and 12 months. To our knowledge, this is the first case of calcinosis circumscripta in a bird involving a limb extremity, similar to the presentation recognized more commonly in domestic animals. Calcinosis circumscripta should be included in the differential diagnosis list for nodular masses attached to the tendons in birds.

  5. Patellar tendon strain is increased at the site of the jumper's knee lesion during knee flexion and tendon loading: results and cadaveric testing of a computational model.

    Science.gov (United States)

    Lavagnino, Michael; Arnoczky, Steven P; Elvin, Niell; Dodds, Julie

    2008-11-01

    Patellar tendinopathy (jumper's knee) is characterized by localized tenderness of the patellar tendon at its origin on the inferior pole of the patella and a characteristic increase in signal intensity on magnetic resonance imaging at this location. However, it is unclear why the lesion typically occurs in this area of the patellar tendon as surface strain gauge studies of the patellar tendon through the range of motion have produced conflicting results. The predicted patellar tendon strains that occur as a result of the tendon loads and patella-patellar tendon angles (PPTAs) experienced during a jump landing will be significantly increased in the area of the patellar tendon associated with patellar tendinopathy. Descriptive laboratory study. A 2-dimensional, computational, finite element model of the patella-patellar tendon complex was developed using anatomic measurements taken from lateral radiographs of a normal knee. The patella was modeled with plane strain rigid elements, and the patellar tendon was modeled with 8-node plane strain elements with neo-Hookean material properties. A tie constraint was used to join the patellar tendon and patella. Patella-patellar tendon angles corresponding to knee flexion angles between 0 degrees and 60 degrees and patellar tendon strains ranging from 5% to 15% were used as input variables into the computational model. To determine if the location of increased strain predicted by the computational model could produce isolated tendon fascicle damage in that same area, 5 human cadaveric patella-patellar tendon-tibia specimens were loaded under conditions predicted by the model to significantly increase localized tendon strain. Pre- and posttesting ultrasound images of the patella-patellar tendon specimens were obtained to document the location of any injured fascicles. Localized tendon strain at the classic location of the jumper's knee lesion was found to increase in association with an increase in the magnitude of applied

  6. In-depth imaging and quantification of degenerative changes associated with Achilles ruptured tendons by polarization-sensitive optical coherence tomography

    Energy Technology Data Exchange (ETDEWEB)

    Bagnaninchi, P O; Yang, Y; Maffulli, G; El Haj, A; Maffulli, N [Institute for Science and Technology in Medicine, Keele University, Thornburrow Drive, Hartshill, Stoke-on-Trent ST4 7QB (United Kingdom); Bonesi, M; Meglinski, I [Cranfield Health, Cranfield University, Cranfield MK43 0AL (United Kingdom); Phelan, C, E-mail: pierre.bagnaninchi@ed.ac.u [Department of Pathology, University Hospital of North Staffordshire, Stoke-on-Trent ST4 7QB (United Kingdom)

    2010-07-07

    The objective of this study was to develop a method based on polarization-sensitive optical coherent tomography (PSOCT) for the imaging and quantification of degenerative changes associated with Achilles tendon rupture. Ex vivo PSOCT examinations were performed in 24 patients. The study involved samples from 14 ruptured Achilles tendons, 4 tendinopathic Achilles tendons and 6 patellar tendons (collected during total knee replacement) as non-ruptured controls. The samples were imaged in both intensity and phase retardation modes within 24 h after surgery, and birefringence was quantified. The samples were fixed and processed for histology immediately after imaging. Slides were assessed twice in a blind manner to provide a semi-quantitative histological score of degeneration. In-depth micro structural imaging was demonstrated. Collagen disorganization and high cellularity were observable by PSOCT as the main markers associated with pathological features. Quantitative assessment of birefringence and penetration depth found significant differences between non-ruptured and ruptured tendons. Microstructure abnormalities were observed in the microstructure of two out of four tendinopathic samples. PSOCT has the potential to explore in situ and in-depth pathological change associated with Achilles tendon rupture, and could help to delineate abnormalities in tendinopathic samples in vivo.

  7. Tendon healing: an experimental model in the dog.

    Science.gov (United States)

    McDowell, C L; Snyder, D M

    1977-03-01

    Based upon the studies of the healing process in dogs in which profundus tendons were severed partially by a method in which the cut surfaces remained in contact and the area of division was in an undamaged area of the sheath, it was shown that healing of the tendon took place without evidence of vascular contribution from the sheath. Vascular loop patterns, similar to those seen in synovial lining of joints or on either side of the growth plate of growing bone, were found on the surface of the tendons in the area of mesotenon reflection, the osseotendinous junctions, where the vinculum joined the tendon, and in various areas of the tendon sheath. No other vessels were found. A theory for nutrition of the tendon is proposed analagous to that postulated for maintenance of cartilage, first with the formation of synovial fluid by the vascular loop system and then a diffusion phase dependent upon the repetitive loading and unloading of the tissue to force the fluid into the system of canaliculi in the tendon.

  8. Quantification of regional blood flow to canine flexor tendons

    Energy Technology Data Exchange (ETDEWEB)

    Weidman, K.A.; Simonet, W.T.; Wood, M.B.; Cooney, W.P.; Ilstrup, D.M.

    1984-01-01

    Although the blood supply and the microcirculation of flexor tendons have been studied and defined extensively using qualitative methods, the quantitative assessment of blood flow has been lacking because of the limitations of the available experimental techniques. The authors studied the regional blood supply to the flexor tendons of dogs by the technique of radionuclide-labeled microspheres. Seven adult mongrel dogs were used. Microsphere injection and tissue-counting techniques previously used for other tissues were applied. Samples of proximal, isthmus, and distal portions of the profundus and superficialis flexor tendons were harvested from each digital unit of available limbs from each dog. Mean (+/- SE) flows (ml/100 g dry tissue/min) were proximal profundus 1.78 +/- 0.60 and superficialis 7.10 +/- 1.50. The differences were significant. The study suggests that regional variation in blood flow to canine digital flexor tendons exists, so that a single value for blood flow to these tendons is not relevant. Furthermore, the study supports the concept of dual (vascular and synovial) nutrition to the digital flexor tendons in dogs. These observations may have implications regarding tendon repair techniques.

  9. Quantification of regional blood flow to canine flexor tendons.

    Science.gov (United States)

    Weidman, K A; Simonet, W T; Wood, M B; Cooney, W P; Ilstrup, D M

    1984-01-01

    Although the blood supply and the microcirculation of flexor tendons have been studied and defined extensively using qualitative methods, the quantitative assessment of blood flow has been lacking because of the limitations of the available experimental techniques. We studied the regional blood supply to the flexor tendons of dogs by the technique of radionuclide-labeled microspheres. Seven adult mongrel dogs were used. Microsphere injection and tissue-counting techniques previously used for other tissues were applied. Samples of proximal, isthmus, and distal portions of the profundus and superficialis flexor tendons were harvested from each digital unit of available limbs from each dog. Mean (+/- SE) flows (ml/100 g dry tissue/min) were proximal profundus 1.78 +/- 0.60 and superficialis 7.10 +/- 1.50. The differences were significant (p less than 0.01). The study suggests that regional variation in blood flow to canine digital flexor tendons exists, so that a single value for blood flow to these tendons is not relevant. Furthermore, the study supports the concept of dual (vascular and synovial) nutrition to the digital flexor tendons in dogs. These observations may have implications regarding tendon repair techniques.

  10. Anatomical repair of zone 1 flexor tendon injuries.

    Science.gov (United States)

    Teo, T C; Dionyssiou, Dimitrios; Armenio, Andrea; Ng, Darren; Skillman, Joanna

    2009-02-01

    Repair and rehabilitation of the flexor digitorum profundus tendon in zone I may be demanding. The aim of the authors' study was to assess a new technique for reinsertion of the distal flexor digitorum profundus tendon. The authors' series consisted of 18 patients who required primary (n = 10) or secondary (n = 8) repair of the flexor digitorum profundus tendon in zone I. A half-Bruner incision was extended into the distal volar skin to expose the insertion site. Two drill holes were made through the base of the distal phalanx obliquely from the insertion of the profundus tendon in a dorsolateral direction. A modified Kessler suture was passed through the tendon and then through these holes and tied anteriorly, providing transosseous, internal fixation. Range of movement was assessed according to Moiemen's categories. Fourteen patients had excellent or good results, two patients had fair results, and one patient had a poor result. One patient failed to complete physiotherapy and was lost to follow-up. No tendon rupture was documented during a mean follow-up period of 8 months. The authors' technique anchors the flexor digitorum profundus tendon or the graft in an anatomical position on the distal phalanx, without the need for external sutures or additional incisions. Furthermore, this is accomplished with minimal morbidity to the surrounding highly specialized tissue. The authors' results compare favorably with those of other techniques in the literature.

  11. Endoscopy-assisted percutaneous repair of acute Achilles tendon tears.

    Science.gov (United States)

    Chiu, Chih-Hao; Yeh, Wen-Lin; Tsai, Min-Chien; Chang, Shih-Sheng; Hsu, Kuo-Yao; Chan, Yi-Sheng

    2013-08-01

    We developed a technique for endoscopy-assisted percutaneous repair of acute Achilles tendon tears. Nineteen patients with acute Achilles tendon tears were prospectively recruited into the study. All patients (18 male, 1 female) had sports-related injuries. Preoperative diagnosis was made from patient history, physical examination, and sonography. The average patient age was 38.7 years, and follow-up averaged 24 months. All patients received endoscopy-assisted percutaneous Achilles tendon repair with modified Bunnell sutures passed by bird beak and No. 5 Ethibond under direct visualization using 4.0-mm arthroscopy. Results were evaluated by physical examination, sonography, and magnetic resonance imaging (MRI). All 19 patients achieved tendon healing. All patients were evaluated by sonography, and the tendons of 16 patients were imaged using MRI to evaluate the extent of healing. Final dorsiflexion was 16 degrees and plantar flexion 26 degrees, and 95% of the patients (18/19) returned to their previous level of sporting activity. One patient developed a superficial infection, and 2 patients had postoperative sural nerve injury with numbness for 1 month. There were no other major complications. Endoscopy-assisted percutaneous repair of the Achilles tendon allowed good tendon healing and return to sports at 6 months. Sural nerve injury during surgery was a potential complication of this procedure. Level IV, retrospective case series.

  12. Tendon shift in hallux valgus: observations at MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Eustace, S. [Department of Radiology, Boston University Medical Center Hospital, 88 East Newton Street, Atrium - 2, Boston, MA 02118 (United States); Williamson, D. [Department of Radiology, Brigham and Womens Hospital, Boston, Massachusetts (United States); Wilson, M. [Department of Orthopedics, Brigham and Womens Hospital, Boston, Massachusetts (United States); O`Byrne, J. [Department of Radiology, Boston University Medical Center Hospital, 88 East Newton Street, Atrium - 2, Boston, MA 02118 (United States); Bussolari, L. [Department of Radiology, Brigham and Womens Hospital, Boston, Massachusetts (United States); Thomas, M. [Department of Radiology, Brigham and Womens Hospital, Boston, Massachusetts (United States); Stephens, M. [Department of Radiology, Boston University Medical Center Hospital, 88 East Newton Street, Atrium - 2, Boston, MA 02118 (United States); Stack, J. [Department of Radiology, Boston University Medical Center Hospital, 88 East Newton Street, Atrium - 2, Boston, MA 02118 (United States); Weissman, B. [Department of Radiology, Brigham and Womens Hospital, Boston, Massachusetts (United States)

    1996-08-01

    Objective. This study was undertaken to demonstrate a shift in tendon alignment at the first metatarsophalangeal joint in patients with hallux valgus by means of magnetic resonance imaging. Design. Ten normal feet and 20 feet with the hallux valgus deformity conforming to conventional clinical and radiographic criteria were prospectively studied using magnetic resonance imaging. Correlation was made between tendon position at the first metatarsophalangeal joint and the severity of the hallux valgus deformity. Results. There is a significant shift in tendon position at the first metatarsophalangeal joint of patients with hallux valgus. The insertion of the abductor hallucis tendon is markedly plantarward and the flexor and extensor tendons bowstring at the first metatarsophalangeal joint compared with patients without the deformity. The severity of the tendon shift correlates with the hallux valgus angle and clinical severity of the hallux valgus deformity in each case. Conclusion. Patients with hallux valgus have a significant tendon shift at the first metatarsophalangeal joint which appears to contribute to development of the deformity. (orig.). With 4 figs., 1 tab.

  13. The histology of tendon attachments to bone in man.

    Science.gov (United States)

    Benjamin, M; Evans, E J; Copp, L

    1986-12-01

    Based on a parallel study of a wide range of human tendons from embalmed dissecting room subjects and from a study of dried bones, an explanation is offered for the well known similarity in gross appearance between the markings left by certain tendons (e.g. those of the rotator cuff) and by articular surfaces on dried bones. Epiphyseal tendons leave markings on bones that look like those left by articular surfaces. These tendons have a prominent zone of fibrocartilage at their attachment site and the deepest part of this is calcified, just as the deepest part of articular hyaline cartilage is calcified. After maceration of the soft tissues, the calcified (fibro) cartilage is left attached to the bone at articular surfaces and at the sites of tendon attachment. In all cases, the tissues separate at the basophilic tidemark between the calcified and uncalcified regions. This tidemark is smooth where there is much overlying uncalcified (fibro) cartilage and it is the smoothness that gives the typical appearance of the dried bone. Blood vessels do not generally traverse the tendon fibrocartilage plugs. Hence the areas are devoid of vascular foramina. The functional significance of tendon fibrocartilage is discussed with particular reference to supraspinatus. It is suggested that the uncalcified fibrocartilage ensures that the tendon fibres do not bend, splay out or become compressed at a hard tissue interface, and are thereby offered some protection from wear and tear. It is also suggested that the fibrocartilage plug of supraspinatus prevents the tendon from rubbing on the head of the humerus.

  14. Early Passive Movement in flexor tendon injuries of the hand.

    Science.gov (United States)

    Quadlbauer, S; Pezzei, Ch; Jurkowitsch, J; Reb, P; Beer, T; Leixnering, M

    2016-02-01

    Flexor tendon injuries are underestimated considering their anatomical function in the hand. According to the publications of Kleinert, Verdan and Kessler, primary suturing of the flexor tendon combined with immediate postoperative physiotherapy in terms of "Early Passive Movement" became the standard form of therapy following acute flexor tendon injuries of the hand. In a study between 2007 and 2009, a total of 115 flexor tendon injuries were analysed retrospectively. All patients were treated using a two-strand repair technique according to Zechner. They received physiotherapy from the first postoperative day according to the Viennese flexor tendon rehabilitation protocol. For statistical purposes, the factors: age, gender, range of motion (ROM), follow up interval, affected flexor tendon and zone were analysed. The time between injury and surgery was also determined, classified into groups and included in the study. On the basis of the range of motion AROM, the Buck-Gramcko and modified Strickland Score was calculated. The mean follow-up interval was 7 months. Using the Buck-Gramcko and Strickland Score an "excellent" overall result was achieved. Complications occurred in 3.5 %, one secondary rupture (0.9 %), two tendon adhaesions requiring tenolysis (1.7 %) and one case of infection (0.9 %). The time interval between injury and operation, gender, affected zone, flexor tendon and affected finger nerve had no influence on the Buck-Gramcko and Strickland Score. Using Zechner's core suture technique as the primary treatment, combined with immediate postoperative physiotherapy in terms of "Early Passive Movement" according to the Viennese flexor tendon rehabilitation programme, an excellent clinical outcome and low complication rate was acchieved. IV: case series.

  15. The role of proximal pulleys in preventing tendon bowstringing: pulley rupture and tendon bowstringing.

    Science.gov (United States)

    Leeflang, S; Coert, J H

    2014-06-01

    The aim of this study was to investigate factors that contribute to tendon bowstringing at the proximal phalanx. We hypothesised that: (1) a partial rupture of the A2 pulley leads to significant bowstringing, (2) the location of the A2 rupture, starting proximally or distally, influences bowstringing, (3) an additional A3 pulley rupture causes a significant increase in bowstringing following a complete A2 pulley rupture and (4) the skin and tendon sheath may prevent bowstringing in A2 and A3 pulley ruptures. Index, middle and ring fingers of eight freshly frozen cadaver arms were used. A loading device pulled with 100 N force was attached to the flexor digitorum profundus (FDP). The flexor digitorum superficialis (FDS) was preloaded with 5 N. Bowstringing was measured and quantified by the size of the area between the FDP tendon and the proximal phalanx over a distance of 5 mm with ultrasonography (US). US images showed that already a 30% excision of the A2 pulley resulted in significant bowstringing. In addition, a partial distal incision of the A2 pulley showed significantly more bowstringing compared to a partial proximal incision. Additional A3 pulley incision and excision of the proximal tendon sheath did not increase bowstringing. Subsequently, removing the skin did increase the bowstringing significantly. A partial A2 pulley rupture causes a significant bowstringing. A partial rupture of the A2 pulley at the distal rim of the A2 pulley resulted in more bowstringing than a partial rupture at the proximal rim. Copyright © 2014 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  16. Methods of Assessing Human Tendon Metabolism and Tissue Properties in Response to Changes in Mechanical Loading

    DEFF Research Database (Denmark)

    Heinemeier, Katja M; Kjaer, Michael; Magnusson, S Peter

    2016-01-01

    In recent years a number of methodological developments have improved the opportunities to study human tendon. Microdialysis enables sampling of interstitial fluid in the peritendon tissue, while sampling of human tendon biopsies allows direct analysis of tendon tissue for gene- and protein......)), and tendon mechanical properties (ultrasonography combined with force measurement during movement). Finally, 3D cell cultures of human tendon cells provide the opportunity to investigate cell-matrix interactions in response to various interventions....

  17. Endoscopic Resection of Gouty Tophus of the Patellar Tendon

    OpenAIRE

    Lui, Tun Hing

    2015-01-01

    Tophaceous deposition of tendon can result in spontaneous patellar tendon rupture. Surgical therapy may be needed to control symptoms and prevent tendon rupture. Open debridement of the lesion requires a lengthy incision over the lesion; this may result in symptomatic scar adhesion of the patellar tendon or an unhealed wound with persistent tophaceous discharge. Moreover, the other part of the patellar tendon cannot be examined through the incision. We describe a technique for endoscopic rese...

  18. Giant cell tumour of extensor tendon sheath: Preventing recurrence

    Directory of Open Access Journals (Sweden)

    S S Shirol

    2012-01-01

    Full Text Available Giant Cell Tumour of tendon sheath is relatively rare tumour with an overall incidence of around 1 in 50,000 individuals. Marginal excision of giant cell tumour of the tendon sheath is the treatment of choice. It is also the commonest hand lesion to recur after excision. The incidence of local recurrence is high, ranging from 9-44%. Here we present a case report of a giant cell tumour of extensor tendon sheath in hand which was successfully treated with special emphasis on ways of prevention of recurrence.

  19. Adductor longus tendon rupture mistaken for incarcerated inguinal hernia.

    Science.gov (United States)

    Aerts, Bas R J; Plaisier, Peter W; Jakma, Tijs S C

    2014-03-01

    An incarcerated inguinal hernia is a common diagnosis, since the risk of an inguinal hernia incarcerating or strangulating is around 0.3-3%. An acute rupture of the adductor longus tendon is rarely seen and mostly affects (semi-) professional sportsmen. We present a case of a patient with an assumed incarcerated inguinal hernia which turned out to be a proximal adductor longus tendon rupture. If patients without a history of inguinal hernia present themselves with acute groin pain after suddenly exorotating the upper leg, a rupture of the adductor longus tendon should be considered. Both surgical and non-surgical treatment can be performed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Gender Differences in Outcome After an Acute Achilles Tendon Rupture

    OpenAIRE

    Silbernagel, Karin Gravare; Nilsson-Helander, Katarin; Olsson, Nicklas; Brorsson, Annelie; Eriksson, Bengt I; Karlsson, Jon

    2014-01-01

    Objectives: There is an indication in the literature that there is a difference in tendon healing between genders. However comparisons in outcome are often not possible due to the small sample size of women with an acute Achilles tendon rupture. In most studies on patients with Achilles tendon rupture the women only account for less then 20% of the patients. The objective of this study was to evaluate if there are any differences in outcome between genders when combining the data from two lar...

  1. Tendon collagen synthesis declines with immobilization in elderly humans

    DEFF Research Database (Denmark)

    Dideriksen, Kasper; Boesen, Anders P; Reitelseder, Søren

    2017-01-01

    -80 yr) were randomly assigned to NSAIDs (ibuprofen 1,200 mg/day; Ibu) or placebo (Plc). One lower limb was immobilized in a cast for 2 wk and retrained for 6 wk. Tendon collagen protein synthesis, mechanical properties, size, expression of genes related to collagen turnover and remodeling, and signal...... intensity (from magnetic resonance imaging) were investigated. Tendon collagen synthesis decreased (P ... immobilization in both groups, whereas scleraxis mRNA decreased with inactivity in the Plc group only (P collagen protein synthesis decreased after 2 wk of immobilization, whereas tendon stiffness and modulus were only marginally reduced, and NSAIDs had no influence upon this...

  2. Ultrasound-based testing of tendon mechanical properties

    DEFF Research Database (Denmark)

    Seynnes, O R; Bojsen-Møller, J.; Albracht, K

    2015-01-01

    In the past 20 years, the use of ultrasound-based methods has become a standard approach to measure tendon mechanical properties in vivo. Yet the multitude of methodological approaches adopted by various research groups probably contribute to the large variability of reported values. The technique......, or signal synchronization; and 2) in physiological considerations related to the viscoelastic behavior or length measurements of tendons. Hence, the purpose of the present review is to assess and discuss the physiological and technical aspects connected to in vivo testing of tendon mechanical properties...

  3. Radial forearm flap plus Flexor Carpi Radialis tendon in Achilles tendon reconstruction: Surgical technique, functional results, and gait analysis.

    Science.gov (United States)

    Innocenti, Marco; Tani, Massimiliano; Carulli, Christian; Ghezzi, Serena; Raspanti, Andrea; Menichini, Giulio

    2015-11-01

    Wound dehiscence, infection, and necrosis of tendon and overlying skin are severe complications after open repairs of Achilles tendon. A simultaneous reconstruction should be provided in a single stage operation. We evaluated the outcomes of one of the possible options: the radial forearm free flap with Flexor Carpi Radialis (FCR) tendon. Between 2006 and 2014, six patients affected by infection and necrosis after Achilles tendon open repair underwent multi-tissutal reconstruction by a composite radial forearm free flap including a vascularized FCR tendon. The mean skin and tendon defect was respectively 9.8 cm × 4.7 cm and 6.5 cm. After reconstruction, patients underwent clinical examination, including the Achilles Tendon Total Rupture Score (ATRS) questionnaire, DASH score, MRI study, and a computer-assisted gait analysis. All flaps survived and no complications were recorded. Full weightbearing was allowed within 2 months after surgery. The mean follow-up was 36.2 months (range 12-96). MRI showed an optimal reconstruction of the tendon. Range of motion was minimally reduced if compared to the contralateral side. Gait analysis showed the recovery of a nearly symmetrical stance phase, time to heel off, and step length of the gate. ATRS and DASH score improved to a mean value of 85.2 (range 83-88) and 8.0 (range 3-15) respectively. This procedure provided an anatomical reconstruction of the Achilles tendon and skin achieving good and objective functional results; donor site morbidity was limited to the sacrifice of the radial artery, which, in our opinion, is a minor drawback if compared to the quality of the results. © 2015 Wiley Periodicals, Inc.

  4. The high variability of the chiasma plantare and the long flexor tendons: Anatomical aspects of tendon transfer in foot surgery.

    Science.gov (United States)

    Pretterklieber, Bettina

    2017-05-01

    As tendon transfer of the flexor hallucis longus (FHL) and the flexor digitorum longus (FDL) is an established procedure, exact knowledge of the formation of the chiasma plantare is of great interest. Although the quadratus plantae (QP) appears to play a major role, it has been rarely addressed in previous studies. The aim of the present study was to reinvestigate the formation of the chiasma plantare and the composition of the long flexor tendons in order to clarify the inexact and partly contradictory descriptions published from 1865 onward. The chiasma plantare and the long flexor tendons in both feet of 50 formalin-fixed specimens of body donors (25 men and women) were analyzed by gross anatomical dissection. It was composed of one (3%), two (69%) or three layers (28%) which were variably established by the tendinous and muscular fibers of the FHL, the FDL and the QP. In 61% the FHL gave one or more slips to the FDL, and in 39% there was a bidirectional interconnection between the two tendons. The slip from the FHL to the FDL largely reinforces the second (45%), or the second and third tendon (46%). Thus, the FHL is involved in the first tendon in all cases, in the second one in 97% of cases, and in the third tendon in about one half of cases (53%). In all instances, the FDL contributes to the third to fourth, in 98% the second, and in at least 39% to the first tendon. The QP reinforces the second to fourth tendon in nearly all cases, the fifth in about one half of cases, and even the first tendon in 14% of cases. In addition, the individual composition of the five long flexor tendons arising from the chiasma plantare was analyzed in detail. Special emphasis was placed on the evaluation of side and sex differences as well as individual symmetry. Furthermore, biomechanical, developmental and phylogenetic aspects were outlined. In terms of the outcome of this study, the FHL appears to be the better donor for tendon transfer to restore lost function, but

  5. Fibroma of the tendon sheath--a rare hand tumor following repetitive trauma to the palm.

    Science.gov (United States)

    Yousaf, Muhammad

    2014-01-01

    Fibroma of the tendon sheath (FTS) is a rare, benign, soft tissue lesion. Clinically, FTS presents similarly to the more common giant cell tumour of the tendon sheath. It can be distinguished histologically by the lack of giant cells, foamy histiocytes and synovial cells. The author presents a case of FTS involving the flexor tendon to the fourth metacarpal following repetitive trauma. A 42 year old man presented with a three year history of painless mass in the right palm that had increased in size and became painful recently. Examination demonstrated 6 x 4 cm firm, nodular, superficial mass that was adherent to the underlying structures. Radiographs revealed soft tissue mass. Ultrasound showed a solid heterogeneous mass and the MRI demonstrated that the mass cantered predominantly at the mid and distal portion of fourth metacarpal. Fine Needle Aspiration Cytology was inconclusive. The patient underwent excisional biopsy of the lesion showing lobulated lesion closely resembling hyalinized collagen. Neither vascular proliferations, necrosis, nor mitoses were observed. A diagnosis of FTS was made. The case report provided an additional rare case to literature of a FTS and highlights the need to consider this entity in the differential diagnosis of any soft tissue lesion in the hand after repetitive trauma. Two months later the patient demonstrated full range of movements in the hand.

  6. Exoskeleton anchoring to tendon cells and muscles in molting isopod crustaceans

    Directory of Open Access Journals (Sweden)

    Nada Žnidaršič

    2012-03-01

    Full Text Available Specialized mechanical connection between exoskeleton and underlying muscles in arthropods is a complex network of interconnected matrix constituents, junctions and associated cytoskeletal elements, which provides prominent mechanical attachment of the epidermis to the cuticle and transmits muscle tensions to the exoskeleton. This linkage involves anchoring of the complex extracellular matrix composing the cuticle to the apical membrane of tendon cells and linking of tendon cells to muscles basally. The ultrastructural arhitecture of these attachment complexes during molting is an important issue in relation to integument integrity maintenance in the course of cuticle replacement and in relation to movement ability. The aim of this work was to determine the ultrastructural organization of exoskeleton – muscles attachment complexes in the molting terrestrial isopod crustaceans, in the stage when integumental epithelium is covered by both, the newly forming cuticle and the old detached cuticle. We show that the old exoskeleton is extensively mechanically connected to the underlying epithelium in the regions of muscle attachment sites by massive arrays of fibers in adult premolt Ligia italica and in prehatching embryos and premolt marsupial mancas of Porcellio scaber. Fibers expand from the tendon cells, traverse the new cuticle and ecdysal space and protrude into the distal layers of the detached cuticle. They likely serve as final anchoring sites before exuviation and may be involved in animal movements in this stage. Tendon cells in the prehatching embryo and in marsupial mancas display a substantial apicobasally oriented transcellular arrays of microtubules, evidently engaged in myotendinous junctions and in apical anchoring of the cuticular matrix. The structural framework of musculoskeletal linkage is basically established in described intramarsupial developmental stages, suggesting its involvement in animal motility within the marsupium.

  7. Human multipotent mesenchymal stem cells improve healing after collagenase tendon injury in the rat.

    Science.gov (United States)

    Machova Urdzikova, Lucia; Sedlacek, Radek; Suchy, Tomas; Amemori, Takashi; Ruzicka, Jiri; Lesny, Petr; Havlas, Vojtech; Sykova, Eva; Jendelova, Pavla

    2014-04-09

    Mesenchymal stromal cells attract much interest in tissue regeneration because of their capacity to differentiate into mesodermal origin cells, their paracrine properties and their possible use in autologous transplantations. The aim of this study was to investigate the safety and reparative potential of implanted human mesenchymal stromal cells (hMSCs), prepared under Good Manufacturing Practice (GMP) conditions utilizing human mixed platelet lysate as a culture supplement, in a collagenase Achilles tendon injury model in rats. Eighty-one rats with collagenase-induced injury were divided into two groups. The first group received human mesenchymal stromal cells injected into the site of injury 3 days after lesion induction, while the second group received saline. Biomechanical testing, morphometry and semiquantitative immunohistochemistry of collagens I, II and III, versican and aggrecan, neovascularization, and hMSC survival were performed 2, 4, and 6 weeks after injury. Human mesenchymal stromal cell-treated rats had a significantly better extracellular matrix structure and a larger amount of collagen I and collagen III. Neovascularization was also increased in hMSC-treated rats 2 and 4 weeks after tendon injury. MTCO2 (Cytochrome c oxidase subunit II) positivity confirmed the presence of hMSCs 2, 4 and 6 weeks after transplantation. Collagen II deposits and alizarin red staining for bone were found in 6 hMSC- and 2 saline-treated tendons 6 weeks after injury. The intensity of anti-versican and anti-aggrecan staining did not differ between the groups. hMSCs can support tendon healing through better vascularization as well as through larger deposits and better organization of the extracellular matrix. The treatment procedure was found to be safe; however, cartilage and bone formation at the implantation site should be taken into account when planning subsequent in vivo and clinical trials on tendinopathy as an expected adverse event.

  8. MR imaging of subscapularis tendon injury in the setting of anterior shoulder dislocation

    Energy Technology Data Exchange (ETDEWEB)

    Gyftopoulos, Soterios; Carpenter, Elizabeth; Kazam, Jonathan; Babb, James; Bencardino, Jenny [NYU Hospital for Joint Diseases, New York, NY (United States)

    2012-11-15

    To evaluate the degree and location patterns of subscapularis tendon injury in patients with prior anterior shoulder dislocation (ASD). Forty-five consecutive MR shoulder examinations in patients with a history of ASD and 20 consecutive MR examinations in patients without prior dislocation were reviewed. Two readers assessed for the presence and location of tendinosis and tearing in the subscapularis tendon, which was divided into three segments: superior, middle, and inferior. The readers also documented the presence of anterior labral tears, osseous Bankart defects and Hill-Sachs lesions. Fisher's exact tests were performed to analyze the different types of pathology and their locations. Subscapularis tendinosis, and partial thickness and full thickness tears were more common in patients with a history of ASD. Tendinosis was found in 60-64.4% of the dislocation patients compared with 40% of the non-dislocation group. When stratified by location, the middle and inferior thirds were the most commonly affected with statistical significance (p < 0.05) found in tearing of the inferior third. Anterior labral tears, osseous Bankart defects, and Hill-Sachs lesions were more common in the dislocation group with statistically significant associations with tendinosis in the middle and inferior thirds and tearing of the middle third (p < 0.05). Our study suggests an association between middle and inferior subscapularis tendon pathology and prior anterior shoulder dislocation. Based on our results, careful MR assessment of the subscapularis tendon by the radiologist is indicated in the setting of ASD as injury of this structure can be symptomatic and may be amenable to treatment. (orig.)

  9. Calcific Tendonitis of the Rotator Cuff: An Unusual Case

    Directory of Open Access Journals (Sweden)

    Yasuhiro Mitsui

    2012-01-01

    Full Text Available Few case reports have described the surgical treatment of calcifying tendonitis of the subscapularis tendon. We present a case of symptomatic diffuse calcifying tendonitis involving the subscapularis and infraspinatus insertions that was difficult to detect arthroscopically. The patient was treated with arthroscopic incision of the tendinous insertions thorough removal of the calcific deposits and subsequent repair using a suture-anchor technique. Two years after the surgical procedure, the patient was completely pain-free and attained full range of motion. Radiographic evaluation performed 2 years after the procedure revealed no calcific deposits. We conclude that the combination of incision of the subscapularis and infraspinatus insertions, complete removal of the calcific deposits, and subsequent suture-anchor repair in an all-arthroscopic manner can lead to an excellent clinical outcome without compromising the functional integrity of the rotator cuff tendons.

  10. Protect Your Tendons: Preventing the Pain of Tendinitis

    Science.gov (United States)

    ... steroid injections, or give you a splint or brace. Then gentle exercises can help strengthen the tendon. ... Q&A About Bursitis and Tendinitis Sports Injuries Knee Problems Tendinitis: NIH Health Information NIH Office of ...

  11. A rare knee extensor mechanism injury: Vastus intermedius tendon rupture

    Directory of Open Access Journals (Sweden)

    Engin Cetinkaya

    2015-01-01

    Conclusion: We report the first case of isolated rupture of the vastus intermedius tendon in the literature and we claim that disorder may be succesfully treated with conservative treatment and adequate physiotheraphy.

  12. The Flexor Tendon Pulley System and Rock Climbing

    National Research Council Canada - National Science Library

    Crowley, Timothy

    Rock climbing has increased in popularity over the past two decades. Closed traumatic rupture of the finger flexor tendon pulleys is rare among the general population but is seen much more commonly in rock climbers...

  13. Tendon and ligament adaptation to exercise, immobilization, and remobilization.

    Science.gov (United States)

    Wren, T A; Beaupré, G S; Carter, D R

    2000-01-01

    This study provides a theoretical and computational basis for understanding and predicting how tendons and ligaments adapt to exercise, immobilization, and remobilization. In a previous study, we introduced a model that described the growth and development of tendons and ligaments. In this study, we use the same model to predict changes in the cross-sectional area, modulus, and strength of tendons and ligaments due to increased or decreased loading. The model predictions are consistent with the results of experimental exercise and immobilization studies performed by other investigators. These results suggest that the same fundamental principles guide both development and adaptation. A basic understanding of these principles can contribute both to prevention of tendon and ligament injuries and to more effective rehabilitation when injury does occur.

  14. Adrenergic control of tendon jerk reflexes in man.

    Science.gov (United States)

    Phillips, S J; Richens, A; Shand, D G

    1973-03-01

    1. Tendon jerk responses and H reflexes were recorded from conscious human volunteers before and after intravenous injection of methylamphetamine, thymoxamine and propranolol, and during intravenous infusion of noradrenaline.2. Methylamphetamine produced a significant increase in the amplitude of the tendon jerk, whereas noradrenaline had no effect in doses which caused a greater pressor response than methylamphetamine.3. Thymoxamine produced a dose-related reduction in the tendon jerk.4. Propranolol had no significant effect on the jerk.5. None of these drugs significantly affected the H reflex.6. It is suggested that central adrenoceptors, possibly alpha in type, exist in man, and that stimulation of these receptors facilitates tendon jerk reflexes by an action on the fusimotor system.

  15. Achilles tendon rupture as a result of oral steroid therapy.

    Science.gov (United States)

    Hersh, Bryan L; Heath, Nicholas S

    2002-06-01

    Spontaneous Achilles tendon rupture associated with long-term oral steroid use is not uncommon, particularly in older patients who use these drugs daily to treat systemic diseases. Rupture often results in a large defect, which complicates surgical repair. The authors review Achilles tendon rupture associated with systemic and local steroid use and present a case of rupture due to chronic oral steroid use in a patient with Addison's disease.

  16. Tendon Cell Behavior and Matrix Remodeling in Degenerative Tendinopathy

    OpenAIRE

    Mos, Marieke

    2009-01-01

    textabstractTendon injuries are common in human athletes [1-4]. Furthermore, such injuries are also prevalent in the ageing sedentary population [5-7]. In recent decades, the incidence of tendon injuries has risen due to both an increase in an elderly population and a rise in participation in recreational and competitive sporting activities. In the general population the lifetime cumulative incidence of Achilles tendinopathy is 5.9 % among sedentary people and 50 % among elite endurance athle...

  17. Molecular basis for elastic energy storage in mineralized tendon.

    Science.gov (United States)

    Silver, F H; Freeman, J W; Horvath, I; Landis, W J

    2001-01-01

    Animals store elastic energy in leg and foot tendons during locomotion. In the turkey, much of the locomotive force generated by the gastrocnemius muscle is stored as elastic energy during tendon deformation. Little energy storage occurs within the muscle. During growth of some avians, including the turkey, leg tendons mineralize in the portions distal to the attached muscle and show increased tensile strength and modulus as a result. The purpose of this study is to test the hypothesis that the degree of elastic energy storage in mineralizing turkey tendon is directly related to the tendon mineral content. To test this hypothesis, the stress-strain behavior of tendons was separated into elastic and viscous components. Both the elastic spring constant and the elastic energy stored, calculated up to a strain of 20%, were found to be proportional to tendon mineral content. It is concluded that mineralization is an efficient means for increasing the amount of elastic energy storage that is required for increased load-bearing ability needed for locomotion of adult birds. Examination of molecular models of the hole region, where mineralization is initiated within the collagen fibril, leads to the hypothesis that elastic energy is stored in the tendon by direct stretching of the flexible regions. Flexible regions within the collagen molecule fall within the positively stained bands of the collagen D period. It is proposed that mineralization increases the stored elastic energy by preventing flexible regions within the positively stained bands from stretching. These observations suggest that mineralization begins in the hole region due to the large number of charged amino acid residues found in the d and e bands.

  18. Bilateral Achilles tendon rupture: a report on two cases.

    Science.gov (United States)

    Orava, S; Hurme, M; Leppilahti, J

    1996-10-01

    Two cases of traumatic bilateral Achilles tendon rupture are reported. One of the patients was a healthy middle-aged man, who had been an active national-level gymnast 20 years earlier. He had not suffered any complaints of Achilles tendons before. The ruptures occurred when, after a sauna, he showed his guests a vault forwards, which he had been able to perform easily. This time the landing took place on the toes, causing a high peak stretch to the calf muscles and Achilles tendons. The total rupture of both Achilles tendons was treated surgically, with an excellent result 2 days after the trauma. End-to-end suturation and a fascial flap plasty were made on both sides. No macroscopic degeneration could be detected on the rupture sites. He was allowed to walk freely 6 weeks after the surgery. The second case was a 54-year-old woman, who had suffered from Achilles tendinitis and peritendinitis for 2 years. Both tendons had been surgically treated, and severe adhesions and local degenerative changes had been found. The tendon rupture occurred when she injured her left ankle while getting out of the car. Two days later she fell at home, because of the weakness of the left side, and consequently the right Achilles tendon was injured. She was treated conservatively for 10 days, before the surgery was performed. Both tendons were ruptured and an extensive degeneration of the area was observed. The right side suffered from a rerupture, which was again treated surgically. After surgery the recovery was slow, but the final result 3 years later was moderate. Neither of the patients had any systemic diseases.

  19. The flexor tendon pulley system and rock climbing.

    Science.gov (United States)

    Crowley, Timothy P

    2012-06-01

    Rock climbing has increased in popularity over the past two decades. Closed traumatic rupture of the finger flexor tendon pulleys is rare among the general population but is seen much more commonly in rock climbers. This article reviews the anatomy and biomechanics of the finger flexor tendon pulleys, how they may be injured in rock climbing and how these injuries are best diagnosed and managed.

  20. External post-tensioning of cfrp tendons using integrated sleeve-wedge anchorage

    DEFF Research Database (Denmark)

    Schmidt, Jacob Wittrup; Bennitz, Anders; Goltermann, Per

    2012-01-01

    anchorage was obtained using the novel anchorage and that its behaviour is stable and predicatble when short term static load is applied. Desired strengthening was also observed in external post-tensioning on reinforced concrete T-beams. The requirements and definitions on a stable anchorage of CFRP tendons......Strengthening of structures using external post-tension CFRP systems have proven to be anefficient method as such system increases the structural capacity and reduces cracks and deflection. Sufficient anchorage is of significant importance since the anchorage provides the connection between...

  1. Association of gastrocnemius tendon calcification with chondrocalcinosis of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Foldes, K. [Department of Radiology, Veterans Administration Medical Center (VAMC), San Diego, CA (United States)]|[University of California San Diego Medical Center (UCSD), San Diego, CA (United States)]|[National Institute of Rheumatology and Physiotherapy, Budapest (Hungary); Lenchik, L. [Department of Radiology, Veterans Administration Medical Center (VAMC), San Diego, CA (United States)]|[University of California San Diego Medical Center (UCSD), San Diego, CA (United States); Jaovisidha, S. [Department of Radiology, Veterans Administration Medical Center (VAMC), San Diego, CA (United States)]|[University of California San Diego Medical Center (UCSD), San Diego, CA (United States); Clopton, P. [Department of Radiology, Veterans Administration Medical Center (VAMC), San Diego, CA (United States); Sartoris, D.J. [Department of Radiology, Veterans Administration Medical Center (VAMC), San Diego, CA (United States)]|[University of California San Diego Medical Center (UCSD), San Diego, CA (United States); Resnick, D. [Department of Radiology, Veterans Administration Medical Center (VAMC), San Diego, CA (United States)]|[University of California San Diego Medical Center (UCSD), San Diego, CA (United States)

    1996-10-01

    Objective. Chondrocalcinosis of the knee is a common radiological finding in the elderly. However, visualization of chondrocalcinosis may be difficult in patients with advanced cartilage loss.The purpose of this study was to determine sensitivity, specificity, and accuracy of gastrocnemius tendon calcification that might serve as a radiographic marker of chondrocalcinosis in patients with painful knees. Design and patients. We prospectively evaluated 37 knee radiographs in 30 consecutive patients (29 men, 8 women; mean age 67 years, age range 37-90 years) with painful knees who had radiographic evidence of chondrocalcinosis. The frequency of fibrocartilage, hyaline cartilage, and gastrocnemius tendon calcification was determined. For a control group, we evaluated knee radiographs in 65 consecutive patients with knee pain (54 men, 11 women; mean age 59 years, age range 40-93 years) who had no radiological signs of chondrocalcinosis. The frequency of gastrocnemius tendon calcification in the control group was determined. Results. Gastrocnemius tendon calcification was 41% sensitive, 100% specific, and 78% accurate in predicting chondrocalcinosis. The gastrocnemius tendon was calcified on 15 of 37 (41%) radiographs in the experimental group and on 0 of 67 radiographs in the control group. In the chondrocalcinosis group, 23 (62%) had posterior hyaline cartilage calcification, 14 (38%) had anterior hyaline cartilage calcification, 31 (84%) had medial meniscus calcification, and 36 (97%) had lateral meniscus calcification. Conclusions. Our results show that gastrocnemius tendon calcification is an accurate radiographic marker of chondrocalcinosis in patients with knee pain. (orig.). With 2 figs., 2 tabs.

  2. Biomimetic Scaffold Design for Functional and Integrative Tendon Repair

    Science.gov (United States)

    Zhang, Xinzhi; Bogdanowicz, Danielle; Erisken, Cevat; Lee, Nancy M.; Lu, Helen H.

    2012-01-01

    Rotator cuff tears represent the most common shoulder injuries in the United States. The debilitating effect of this degenerative condition coupled with the high incidence of failure associated with existing graft choices underscore the clinical need for alternative grafting solutions. The two critical design criteria for the ideal tendon graft would require the graft to not only exhibit physiologically relevant mechanical properties but also be able to facilitate functional graft integration by promoting the regeneration of the native tendon-to-bone interface. Centered on these design goals, this review will highlight current approaches to functional and integrative tendon repair. In particular, the application of biomimetic design principles through the use of nanofiber- and nanocomposite-based scaffolds for tendon tissue engineering will be discussed. This review will begin with nanofiber-based approaches to functional tendon repair, followed by a section highlighting the exciting research on tendon-to-bone interface regeneration, with an emphasis on implementation of strategic biomimicry in nanofiber scaffold design and the concomitant formation of graded multi-tissue systems for integrative soft tissue repair. This review will conclude with a summary and future directions section. PMID:22244070

  3. Sex Variation in Patellar Tendon Kinetics During Running

    Directory of Open Access Journals (Sweden)

    Sinclair Jonathan

    2015-06-01

    Full Text Available Purpose. The aim of the current investigation was to determine whether female recreational runners exhibit distinct patellar tendon loading patterns in relation to their male counterparts. Methods. Twelve male (age 26.55 ± 4.11 years, height 1.78 ± 0.11 m, mass 77.11 ± 5.06 kg and twelve female (age 26.67 ± 5.34 years, height 1.67 ± 0.12 m, mass 63.28 ± 9.75 kg runners ran over a force platform at 4.0 m · s-1. Lower limb kinematics were collected using an eight-camera optoelectric motion capture system which operated at 250 Hz. Patellar tendon loads were examined using a predictive algorithm. Sex differences in limb, knee and ankle joint stiffness were examined statistically using independent samples t tests. Results. The results indicate that patellar tendon force (male = 6.49 ± 2.28, female = 7.03 ± 1.35 and patelllar tendon loading rate (male = 92.41 ± 32.51, female = 111.05 ± 48.58 were significantly higher in female runners. Conclusions. Excessive tendon loading in female runners indicates that female runners may be at increased risk of patellar tendon pathologies.

  4. A mathematical model characterising Achilles tendon dynamics in flexion.

    Science.gov (United States)

    Chatzistefani, N; Chappell, M J; Hutchinson, C; Kletzenbauer, S; Evans, N D

    2017-02-01

    The purpose of this study is to acquire mechanistic knowledge of the gastrocnemius muscle-Achilles tendon complex behaviour during specific movements in humans through mathematical modelling. Analysis of this muscle-tendon complex was performed to see if already existing muscle-tendon models of other parts of the body could be applied to the leg muscles, especially the gastrocnemius muscle-Achilles tendon complex, and whether they could adequately characterise its behaviour. Five healthy volunteers were asked to take part in experiments where dorsiflexion and plantar flexion of the foot were studied. A model of the Achilles tendon-gastrocnemius muscle was developed, incorporating assumptions regarding the mechanical properties of the muscle fibres and the tendinous tissue in series. Ultrasound images of the volunteers, direct measurements and additional mathematical calculations were used to parameterise the model. Ground reaction forces, forces on specific joints and moments and angles for the ankle were obtained from a Vicon 3D motion capture system. Model validation was performed from the experimental data captured for each volunteer and from reconstruction of the movements of specific trajectories of the joints, muscles and tendons involved in those movements. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Factors affecting extension lag after tendon reconstruction for finger extensor tendon rupture due to distal radioulnar lesion.

    Science.gov (United States)

    Itsubo, Toshiro; Uchiyama, Shigeharu; Yamazaki, Hiroshi; Hayashi, Masanori; Nakamura, Koichi; Kuniyoshi, Kazuki; Kato, Hiroyuki

    2016-01-01

    Although extensor tendon rupture associated with distal radioulnar joint disorder is often encountered, its treatment has not yet been established. We report the postoperative results for reconstruction of finger extensor tendon rupture due to distal radioulnar lesion and analyse the factors affecting postoperative extension lag. We examined 74 index, middle, ring, or little fingers with extensor tendon rupture of 34 hands. Primary diseases were rheumatoid arthritis in 24 hands and osteoarthritis in 10. Reconstruction methods included tendon graft in 45 fingers, extensor indicis proprius tendon transfer in 15, and end-to-side adjacent tendon suture in 14. At final postoperative follow-up ranging from 12 to 40 (mean: 18) months, we measured metacarpophalangeal (MCP) joint range of motion and extension lag and statistically evaluated the relationship between postoperative extension lag and several clinical factors. We encountered no cases of re-rupture or worsening of finger flexion range after reconstruction. Mean postoperative active flexion of the MCP joint was 78.1 (range: 45-95) degrees. Mean postoperative extension lag was 10.3 (range: 0-50) degrees. We observed that postoperative extension lag was significantly larger in fingers associated with extensor tendon rupture in two or three additional fingers in the affected hand or in fingers of patients aged 80 years or over. The interval from rupture to reconstruction, reconstruction method, or arthritis type did not remarkably affect outcome. This study uncovered that surgical intervention for extensor tendon rupture should be performed before three fingers become affected. Copyright © 2015 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

  6. Tendinopathy of the long head of the biceps tendon: histopathologic analysis of the extra-articular biceps tendon and tenosynovium

    OpenAIRE

    Streit JJ; Shishani Y; Rodgers M; Gobezie R

    2015-01-01

    Jonathan J Streit,1 Yousef Shishani,1 Mark Rodgers,2 Reuben Gobezie1 1The Cleveland Shoulder Institute, 2Department of Pathology, University Hospitals of Cleveland, Cleveland, OH, USA Background: Bicipital tendinitis is a common cause of anterior shoulder pain, but there is no evidence that acute inflammation of the extra-articular long head of the biceps (LHB) tendon is the root cause of this condition. We evaluated the histologic findings of the extra-articular portion of the LHB tendon an...

  7. An in vitro scratch tendon tissue injury model: effects of high frequency low magnitude loading.

    Science.gov (United States)

    Adekanmbi, Isaiah; Zargar, Nasim; Hulley, Philippa

    2017-03-01

    The healing process of ruptured tendons is suboptimal, taking months to achieve tissue with inferior properties to healthy tendon. Mechanical loading has been shown to positively influence tendon healing. However, high frequency low magnitude (HFLM) loads, which have shown promise in maintaining healthy tendon properties, have not been studied with in vitro injury models. Here, we present and validate an in vitro scratch tendon tissue injury model to investigate effects of HFLM loading on the properties of injured rat tail tendon fascicles (RTTFs). A longitudinal tendon tear was simulated using a needle aseptically to scratch a defined length along individual RTTFs. Tissue viability, biomechanical, and biochemical parameters were investigated before and 7 days after culture . The effects of static, HFLM (20 Hz), and low frequency (1 Hz) cyclic loading or no load were also investigated. Tendon viability was confirmed in damaged RTTFs after 7 days of culture, and the effects of a 0.77 ± 0.06 cm scratch on the mechanical property (tangent modulus) and tissue metabolism in damaged tendons were consistent, showing significant damage severity compared with intact tendons. Damaged tendon fascicles receiving HFLM (20 Hz) loads displayed significantly higher mean tangent modulus than unloaded damaged tendons (212.7 ± 14.94 v 92.7 ± 15.59 MPa), and damaged tendons receiving static loading (117.9 ± 10.65 MPa). HFLM stimulation maintained metabolic activity in 7-day cultured damaged tendons at similar levels to fresh tendons immediately following damage. Only damaged tendons receiving HFLM loads showed significantly higher metabolism than unloaded damaged tendons (relative fluorescence units -7021 ± 635.9 v 3745.1 ± 641.7). These validation data support the use of the custom-made in vitro injury model for investigating the potential of HFLM loading interventions in treating damaged tendons.

  8. MRI T2 mapping of the asymptomatic supraspinatus tendon by age and imaging plane using clinically relevant subregions

    Energy Technology Data Exchange (ETDEWEB)

    Anz, Adam W., E-mail: anz.adam.w@gmail.com [The Steadman Clinic, Vail, CO (United States); Lucas, Erin P., E-mail: erin.lucas14@gmail.com [Steadman Philippon Research Institute, Vail, CO (United States); Fitzcharles, Eric K., E-mail: ericfitzcharles@gmail.com [Steadman Philippon Research Institute, Vail, CO (United States); Surowiec, Rachel K., E-mail: Rachel.surowiec@sprivail.org [Steadman Philippon Research Institute, Vail, CO (United States); Millett, Peter J., E-mail: drmillett@thesteadmanclinic.com [The Steadman Clinic, Vail, CO (United States); Ho, Charles P., E-mail: Charles.ho@sprivail.org [Steadman Philippon Research Institute, Vail, CO (United States)

    2014-05-15

    Purpose: Diagnosis of partial rotator cuff tears and tendonopathy using conventional MRI has proven variable. Quantitative T2 mapping may have application for assessing rotator cuff health. In order to evaluate the usefulness of T2 mapping for the rotator cuff, methods must be refined for mapping the supraspinatus tendon, and normative T2 values must first be acquired. Materials and methods: This study was IRB approved. Thirty asymptomatic volunteers (age: 18–62) were evaluated with sagittal and coronal T2 mapping sequences. Manual segmentation of tendon and muscle as a unit and tendon alone was performed twice by two independent raters. Segmentations were divided into medial, middle and lateral subregions and mean T2 values calculated. Results: Anatomic comparison of mean T2 values illustrated highest values in the medial region, lowest values in the lateral region, and intermediate values for the middle region upon coronal segmentation (p < 0.001). In sagittal segmentations, there were higher values in the medial region and no significant differences between the lateral and middle subregions. No significant differences were found with comparison across age groups. Inter and intra-rater segmentation repeatability was excellent, with coefficients ranging from 0.85 to 0.99. Conclusion: T2 mapping illustrated anatomic variation along the supraspinatus muscle-tendon unit with low standard deviations and excellent repeatability, suggesting that changes in structure due to degeneration or changes associated with healing after repair may be detectable.

  9. Effectiveness of the Simultaneous Stretching of the Achilles Tendon and Plantar Fascia in Individuals With Plantar Fasciitis.

    Science.gov (United States)

    Engkananuwat, Phoomchai; Kanlayanaphotporn, Rotsalai; Purepong, Nithima

    2017-10-01

    Since the plantar fascia and the Achilles tendon are anatomically connected, it is plausible that stretching of both structures simultaneously will result in a better outcome for plantar fasciitis. Fifty participants aged 40 to 60 years with a history of plantar fasciitis greater than 1 month were recruited. They were prospectively randomized into 2 groups. Group 1 was instructed to stretch the Achilles tendon while group 2 simultaneously stretched the Achilles tendon and plantar fascia. After 4 weeks of both stretching protocols, participants in group 2 demonstrated a significantly greater pressure pain threshold than participants in group 1 ( P = .040) with post hoc analysis. No significant differences between groups were demonstrated in other variables ( P > .05). Concerning within-group comparisons, both interventions resulted in significant reductions in pain at first step in the morning and average pain at the medial plantar calcaneal region over the past 24 hours, while there were increases in the pressure pain threshold, visual analog scale-foot and ankle score, and range of motion in ankle dorsiflexion ( P plantar fascia for 4 weeks was a more effective intervention for plantar fasciitis. Patients who reported complete relief from symptoms at the end of the 4-week intervention in the simultaneous stretching group (n = 14; 56%) were double that of the stretching of the Achilles tendon-only group (n = 7; 28%). II, lesser quality RCT or prospective comparative study.

  10. The aponeurotic expansion of the supraspinatus tendon: anatomy and prevalence in a series of 150 shoulder MRIs

    Energy Technology Data Exchange (ETDEWEB)

    Moser, Thomas P.; Bureau, Nathalie J. [Centre Hospitalier de l' Universite de Montreal, Department of Radiology and Research Center, Montreal, QC (Canada); Cardinal, Etienne [Radiologie Laennec, Montreal, QC (Canada); Guillin, Raphael [Centre Hospitalier Universitaire de Rennes, Radiology Department, Rennes (France); Lanneville, Pascale [Hopital du Centre-de-la-Mauricie, Pathology Department, Shawinigan, QC (Canada); Grabs, Detlev [Universite du Quebec a Trois-Rivieres, Anatomy Department, Trois-Rivieres, QC (Canada)

    2014-09-02

    To describe the aponeurotic expansion of the supraspinatus tendon with anatomic correlations and determine its prevalence in a series of patients imaged with MRI. In the first part of this HIPAA-compliant and IRB-approved study, we retrospectively reviewed 150 consecutive MRI studies of the shoulder obtained on a 1.5-T system. The aponeurotic expansion at the level of the bicipital groove was classified as: not visualized (type 0), flat-shaped (type 1), oval-shaped and less than 50 % the size of the adjacent long head of the biceps section (type 2A), or oval-shaped and more than 50 % the size of the adjacent long head of the biceps section (type 2B). In the second part of this study, we examined both shoulders of 25 cadavers with ultrasound. When aponeurotic expansion was seen at US, a dissection was performed to characterize its origin and termination. An aponeurotic expansion of the supraspinatus located anterior and lateral to the long head of the biceps in its groove was clearly demonstrated in 49 % of the shoulders with MRI. According to our classification, its shape was type 1 in 35 %, type 2A in 10 % and type 2B in 4 %. This structure was also identified in 28 of 50 cadaveric shoulders with ultrasound and confirmed at dissection in 10 cadavers (20 shoulders). This structure originated from the most anterior and superficial aspect of the supraspinatus tendon and inserted distally on the pectoralis major tendon. The aponeurotic expansion of the supraspinatus tendon can be identified with MRI or ultrasound in about half of the shoulders. It courses anteriorly and laterally to the long head of the biceps tendon, outside its synovial sheath. (orig.)

  11. Anterior transfer of tibialis posterior tendon for treating drop foot: Technique of enforcing tendon implantation to improve success rate.

    Science.gov (United States)

    Wu, Chi-Chuan; Tai, Ching-Lung

    2015-03-01

    An absolutely convincing technique of anterior transfer of the tibialis posterior (TP) tendon for treating drop foot has not been developed. Thirty-seven consecutive adult patients with drop foot owing to deep peroneal nerve injury were treated with bone-to-bone TP tendon transfer. The TP tendon with a small bony attachment was procured from the undersurface of the navicula and then transferred through a tunnel of the interosseous membrane. The navicular attachment was implanted in the tunnel of the navicula or intermediate cuneiform. Cancellous bone graft procured from the distal tibial metaphysis was packed into the tunnel inlet. Side-to-side tendon suturing was performed between the TP tendon and tibialis anterior tendon. Thirty-one patients were followed for a mean of 2.8 years (range, 1.2-4.8 years), and all achieved satisfactory outcome for the ankle. All patients achieved a normal gait after one year and at the latest follow-up. The described technique may provide a high success rate. This surgical technique is not complex, and complications are few.

  12. Augmented Repair of an Achilles Tendon Rupture Using the Flexor Digitorum Lateralis Tendon in a Toy Poodle.

    Science.gov (United States)

    Katayama, Masaaki

    2016-11-01

    To report appositional augmentation of Achilles tendon rupture in a toy breed dog with an intact flexor digitorum lateralis (FDL) muscle tendon. Clinical case report. Two-year-old spayed female Toy Poodle with Achilles tendon rupture. The Achilles tendon was accidentally ruptured by hair clippers during grooming. The dog demonstrated a plantigrade stance without digital flexion of the right hind limb. The ruptured gastrocnemius and superficial digital flexor tendons were sutured to their respective cut ends using a simple locking loop pattern under a surgical microscope. The repair site was appositionally augmented by the caudally retracted intact FDL. An aluminum splint was applied on the plantar aspect to immobilize the tarsal joint for the first 2 weeks, after which a soft bandage was applied for another 2 weeks. At the 7 month follow-up no lameness was detected during walking and no complications associated with decreased FDL function such as digital contracture were observed. The range of motion of the tarsal joint had improved and could be flexed to ∼60° and extended fully. Use of the FDL is feasible for augmenting Achilles tendon repair in toy breed dogs. © Copyright 2016 by The American College of Veterinary Surgeons.

  13. Prolonged stretching of the ankle plantarflexors elicits muscle-tendon adaptations relevant to ankle gait kinetics in children with spastic cerebral palsy.

    Science.gov (United States)

    Martín Lorenzo, Teresa; Rocon, Eduardo; Martínez Caballero, Ignacio; Ramírez Barragán, Ana; Lerma Lara, Sergio

    2017-11-01

    Tissue related ankle hyper-resistance has been reported to contribute to equinus gait in children with spastic cerebral palsy. Hence, ankle plantarflexor stretching programs have been developed in order to restore passive ankle dorsiflexion. Despite high quality evidence on the limited effects of stretching on passive joint mobility, further muscle-tendon adaptations have been reported which may impact gait performance. As such, children with spastic cerebral palsy subject to long-term manual static stretching achieved dorsiflexion gains through the reduction of muscle and fascicle strain whilst preserving tendon strain, and prolonged use of ankle-foot orthoses achieved similar dorsiflexion gains through increased tendon strain whilst preserving muscle and fascicle strain. The latter concurred with normalization of early stance plantarflexor moment yet reductions in push-off plantarflexor moment given the increase in tendon compliance. Therefore, similar limited gains in passive ankle joint mobility in response to stretching may be achieved either by preserving/restoring optimal muscle-tendon function, or at the expense of muscle-tendon function and thus contributing gait impairments. The largest increase in ankle passive joint mobility in children with SCP has been obtained through prolonged plantarflexor stretching through ankle casting combined with botulinum neurotoxin type A. However, to our knowledge, there are no published studies on muscle-tendinous adaptations to ankle casting combined with botulinum toxin type A and its effect on ankle joint gait kinetics. Therefore, we hypothesized that ankle casting elicits muscle-tendon adaptations which concur with altered ankle joint kinetics during the stance phase of gait in children with SCP. More information is needed about the relationships between muscle structure and function, and the effect of specific interventions designed to alter muscle properties and associated functional outcomes in